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http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#UNIX_Shell
UNIX Shell
if2() { if eval "$1"; then if eval "$2"; then eval "$3"; else eval "$4"; fi else if eval "$2"; then eval "$5"; else eval "$6"; fi fi }
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Sidef
Sidef
{ |i| if (i %% 3) { print "Fizz" i %% 5 && print "Buzz" print "\n" } elsif (i %% 5) { say "Buzz" } else { say i } } * 100
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Swift
Swift
import Foundation   func soeDictOdds() -> UnfoldSequence<Int, Int> { var bp = 5; var q = 25 var bps: UnfoldSequence<Int, Int>.Iterator? = nil var dict = [9: 6] // Dictionary<Int, Int>(9 => 6) return sequence(state: 2, next: { n in if n < 9 { if n < 3 { n = 3; return 2 }; defer {n += 2}; return n } while...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#Clojure
Clojure
(ns brainfuck)   (def ^:dynamic *input*)   (def ^:dynamic *output*)   (defrecord Data [ptr cells])   (defn inc-ptr [next-cmd] (fn [data] (next-cmd (update-in data [:ptr] inc))))   (defn dec-ptr [next-cmd] (fn [data] (next-cmd (update-in data [:ptr] dec))))   (defn inc-cell [next-cmd] (fn [data] (next-...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#D
D
import std.stdio, std.random, std.algorithm, std.range, std.ascii;   enum target = "METHINKS IT IS LIKE A WEASEL"d; enum C = 100; // Number of children in each generation. enum P = 0.05; // Mutation probability. enum fitness = (dchar[] s) => target.zip(s).count!q{ a[0] != a[1] }; dchar rnd() { return (uppercase ~ " ")...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#LiveCode
LiveCode
-- Iterative, translation of the basic version. function fibi n put 0 into aa put 1 into b repeat with i = 1 to n put aa + b into temp put b into aa put temp into b end repeat return aa end fibi   -- Recursive function fibr n if n <= 1 then return n else ...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Python
Python
$ "bottles.qky" loadfile ( if required, the source code for this can be found at http://rosettacode.org/wiki/99_bottles_of_beer#Quackery )   [ stack ] is accumulator ( --> s )   [ stack ] is sourcecode ( --> s )   [ say "Hello, world!" cr ] is H.HQ9+ ...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Quackery
Quackery
$ "bottles.qky" loadfile ( if required, the source code for this can be found at http://rosettacode.org/wiki/99_bottles_of_beer#Quackery )   [ stack ] is accumulator ( --> s )   [ stack ] is sourcecode ( --> s )   [ say "Hello, world!" cr ] is H.HQ9+ ...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#PureBasic
PureBasic
Structure mRule pattern.s replacement.s isTerminal.i EndStructure   Procedure parseRule(text.s, List rules.mRule()) #tab = 9: #space = 32: #whiteSpace$ = Chr(#space) + Chr(#tab) Protected tLen, cPtr, nChar.c, pEnd, pLast, pattern.s   cPtr = 1 If FindString(#whiteSpace$, Left(text, cPtr), 1): ProcedureRetu...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Seed7
Seed7
$ include "seed7_05.s7i";   const EXCEPTION: U0 is enumlit; const EXCEPTION: U1 is enumlit;   const proc: baz (in integer: num) is func begin if num = 1 then raise U0; else raise U1; end if; end func;   const proc: bar (in integer: num) is func begin baz(num); end func;   const proc:...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Sidef
Sidef
func baz(i) { die "U#{i}" }; func bar(i) { baz(i) };   func foo { [0, 1].each { |i| try { bar(i) } catch { |_, msg| msg ~~ /^U0/ ? say "Function foo() caught exception U0"  : die msg; # re-raise the exception }; } }   foo();
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Smalltalk
Smalltalk
  Exception subclass: #U0. Exception subclass: #U1.   Object subclass: Foo [   bazCount := 0.   foo [2 timesRepeat: [ "==>" [self bar] "<==" on: U0 do: [:sig | 'Call to bar was aborted by exception U0' printNl. ...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#MATLAB
MATLAB
>> error 'Help' ??? Help
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Modula-3
Modula-3
EXCEPTION EndOfFile; EXCEPTION Error(TEXT);
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Io
Io
System runCommand("ls") stdout println
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#IS-BASIC
IS-BASIC
100 EXT "dir"
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#J
J
load'task'   NB. Execute a command and wait for it to complete shell 'dir'   NB. Execute a command but don't wait for it to complete fork 'notepad'   NB. Execute a command and capture its stdout stdout =: shell 'dir'   NB. Execute a command, provide it with stdin, NB. and capture its stdout stdin =: 'bl...
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#Babel
Babel
((main {(0 1 2 3 4 5 6 7 8 9 10) {fact ! %d nl <<} each})   (fact {({dup 0 =}{ zap 1 } {dup 1 =}{ zap 1 } {1 }{ <- 1 {iter 1 + *} -> 1 - times }) cond}))
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Pascal
Pascal
Program ExponentiationOperator(output);   function intexp (base, exponent: integer): longint; var i: integer;   begin if (exponent < 0) then if (base = 1) then intexp := 1 else intexp := 0 else begin intexp := 1; for i := 1 to exponent do intexp := int...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Ursala
Ursala
iftwo("p","q") <"both","justp","justq","neither"> =   "p"?( "q"?("both","justp"), "q"?("justq","neither"))
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Wren
Wren
class IfBoth { construct new(cond1, cond2) { _cond1 = cond1 _cond2 = cond2 }   elseFirst(func) { if (_cond1 && !_cond2) func.call() return this }   elseSecond(func) { if (_cond2 && !_cond1) func.call() return this }   elseNeither(func) { ...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Simula
Simula
begin integer i; for i := 1 step 1 until 100 do begin boolean fizzed; fizzed := 0 = mod(i, 3); if fizzed then outtext("Fizz"); if mod(i, 5) = 0 then outtext("Buzz") else if not fizzed then outint(i, 3); outimage end; end
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Tcl
Tcl
package require Tcl 8.6   # An iterative version of the Sieve of Eratosthenes. # Effective limit is the size of memory. coroutine primes apply {{} { yield while 1 {yield [coroutine primes_[incr p] apply {{} { yield [info coroutine] set plist {} for {set n 2} true {incr n} { set found 0 foreach p $p...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#CLU
CLU
tape = cluster is new, left, right, get_cell, set_cell ac = array[char] rep = record [ cells: ac, index: int ]   new = proc () returns (cvt) t: rep := rep${ cells: ac$predict(0, 30000), index: 0 } ac$addh(t.cells, '\000') return(t...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#Delphi
Delphi
pragma.syntax("0.9") pragma.enable("accumulator")   def target := "METHINKS IT IS LIKE A WEASEL" def alphabet := "ABCDEFGHIJKLMNOPQRSTUVWXYZ " def C := 100 def RATE := 0.05   def randomCharString() { return E.toString(alphabet[entropy.nextInt(alphabet.size())]) }   def fitness(string) { return accum 0 for i => ch...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#LLVM
LLVM
; This is not strictly LLVM, as it uses the C library function "printf". ; LLVM does not provide a way to print values, so the alternative would be ; to just load the string into memory, and that would be boring.   ; Additional comments have been inserted, as well as changes made from the output produced by clang such ...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Racket
Racket
#lang racket ; if we `for` over the port, we won't have the program in memory for 'Q' (define (parse-HQ9+ the-program) (define oTW " on the wall") (and ; ensures the accumulator is never seen! (for/fold ((A 0)) ((token (in-string the-program))) (case token ((#\H) (display "hello, world") A) ...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Raku
Raku
class HQ9Interpreter { has @!code; has $!accumulator; has $!pointer;   method run ($code) { @!code = $code.comb; $!accumulator = 0; $!pointer = 0; while $!pointer < @!code { given @!code[$!pointer].lc { when 'h' { say 'Hello world!' } ...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Python
Python
import re   def extractreplacements(grammar): return [ (matchobj.group('pat'), matchobj.group('repl'), bool(matchobj.group('term'))) for matchobj in re.finditer(syntaxre, grammar) if matchobj.group('rule')]   def replace(text, replacements): while True: for pat, repl, ter...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Swift
Swift
enum MyException : ErrorType { case U0 case U1 }   func foo() throws { for i in 0 ... 1 { do { try bar(i) } catch MyException.U0 { print("Function foo caught exception U0") } } }   func bar(i: Int) throws { try baz(i) // Nest those calls }   func baz(i: Int) throws { if i == 0 { ...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Tcl
Tcl
package require Tcl 8.5   proc foo {} { set code [catch {bar} ex options] if {$code == 1} { switch -exact -- $ex { U0 {puts "caught exception U0"} default {return -options $options $ex ;# re-raise exception} } } }   proc bar {} {baz}   # create an alias to pass ...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#MOO
MOO
raise(E_PERM);
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Nanoquery
Nanoquery
try invalid "this statement will fail" catch e println "caught an exception" println e end try
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Java
Java
import java.util.Scanner; import java.io.*;   public class Program { public static void main(String[] args) { try { Process p = Runtime.getRuntime().exec("cmd /C dir");//Windows command, use "ls -oa" for UNIX Scanner sc = new Scanner(p.getInputStream()); while (sc.hasNext()) System...
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#JavaScript
JavaScript
var shell = new ActiveXObject("WScript.Shell"); shell.run("cmd /c dir & pause");
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#BaCon
BaCon
' Factorial FUNCTION factorial(NUMBER n) TYPE NUMBER IF n <= 1 THEN RETURN 1 ELSE RETURN n * factorial(n - 1) ENDIF END FUNCTION   n = VAL(TOKEN$(ARGUMENT$, 2)) PRINT n, factorial(n) FORMAT "%ld! = %ld\n"
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Perl
Perl
#!/usr/bin/perl -w use strict ;   sub expon { my ( $base , $expo ) = @_ ; if ( $expo == 0 ) { return 1 ; } elsif ( $expo == 1 ) { return $base ; } elsif ( $expo > 1 ) { my $prod = 1 ; foreach my $n ( 0..($expo - 1) ) { $prod *= $base ; } return $prod ; } el...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#XBS
XBS
#> newsyntax @in:CH @token:does @CH:"function(Stack){ this.Next(Stack); this.ChunkWrite(Stack,this.ParseExpression(Stack)); this.TestNext(Stack,\"Bracket\",\"TK_BOPEN\"); this.Move(Stack,2); this.CodeBlock(Stack); this.JumpBack(Stack); this.OpenChunk(Stack); while(this.CheckNext(Stack,\"Identifier\",\"otherwise...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Z80_Assembly
Z80 Assembly
cp b jr nz,B_False cp c jr z,doubleTrue ;B true, C false   ;your code goes here   jp done B_False: cp c jr nz,doubleFalse ;B false, C true   ;your code goes here   jp done   doubleTrue: ;your code goes here jp done doubleFalse: ;your code goes here jp done   done: ;rest of prog...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#SkookumScript
SkookumScript
  1.to 100 [ println( if idx.mod(15) = 0 ["FizzBuzz"] idx.mod(3) = 0 ["Fizz"] idx.mod(5) = 0 ["Buzz"] else [idx]) ]  
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#VBA
VBA
Option Explicit   Sub Main() Dim Primes() As Long, n As Long, temp$ Dim t As Single t = Timer   n = 133218295 'limit for an Array of Longs with VBA on my computer Primes = ListPrimes(n) Debug.Print "For N = " & Format(n, "#,##0") & ", execution time : " & _ Format(Timer - t, "0.000 s") & ", " & ...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#COBOL
COBOL
pointer_alpha = 1/0 pointer_numeric = 1/0 tape_behind = '' tape_ahead = 1/0 tape_pos = 0 # only for debugging array_behind = 1/0 array_ahead = '' set_tape_ahead = array_ahead array_ahead = 1/0 # shift comefrom if array_ahead is array_ahead cdr = 1/0 cdr = array_ahead shift_tail = cdr new_cell comefrom shi...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#E
E
pragma.syntax("0.9") pragma.enable("accumulator")   def target := "METHINKS IT IS LIKE A WEASEL" def alphabet := "ABCDEFGHIJKLMNOPQRSTUVWXYZ " def C := 100 def RATE := 0.05   def randomCharString() { return E.toString(alphabet[entropy.nextInt(alphabet.size())]) }   def fitness(string) { return accum 0 for i => ch...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#Logo
Logo
to fib :n [:a 0] [:b 1] if :n < 1 [output :a] output (fib :n-1 :b :a+:b) end
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#REXX
REXX
/*REXX program implements the HQ9+ language. ───────────────────────────────────────*/ arg pgm . /*obtain optional argument.*/ accumulator=0 /*assign default to accum. */   do instructions=1 for length(pgm); ...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Racket
Racket
  #lang racket   (struct -> (A B)) (struct ->. (A B))   (define ((Markov-algorithm . rules) initial-string) (let/cc stop  ; rewriting rules (define (rewrite rule str) (match rule [(-> a b) (cond [(replace a str b) => apply-rules] [else str])] [(->. a b) (cond [...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Raku
Raku
grammar Markov { token TOP { ^ [^^ [<rule> | <comment>] $$ [\n|$]]* $ { make $<rule>>>.ast } } token comment { <before ^^> '#' \N* { make Nil } } token ws { [' '|\t]* } rule rule { <before ^^>$<pattern>=[\N+?] '->' $<terminal>=[\.]?$<re...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#TXR
TXR
@(defex u0) @(defex u1) @(define baz (x)) @ (cases) @ (bind x "0") @ (throw u0 "text0") @ (or) @ (bind x "1") @ (throw u1 "text1") @ (end) @(end) @(define bar (x)) @ (baz x) @(end) @(define foo ()) @ (next :list @'("0" "1")) @ (collect) @num @ (try) @ (bar num) @ (catch u0 (arg)) @ (ou...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Ursala
Ursala
#import std   baz =   ~&?( ~&h?(  :/'baz succeeded with this input:', <'baz threw a user-defined empty string exception','U1'>!%), <'baz threw a user-defined empty file exception','U0'>!%)   bar = :/'bar received this result from normal termination of baz:'+ baz   #executable&   foo =   guard(  :/'...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Visual_Basic_.NET
Visual Basic .NET
Class U0 Inherits Exception End Class   Class U1 Inherits Exception End Class   Module Program Sub Main() Foo() End Sub   Sub Foo() Try Bar() Bar() Catch ex As U0 Console.WriteLine(ex.GetType.Name & " caught.") End Try End Sub  ...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Nemerle
Nemerle
// define a new exception class MyException : Exception { ... }   // throw an exception Foo() : void { throw MyException(); }   // catching exceptions try { Foo(); } catch { // catch block uses pattern matching syntax |e is MyException => ... // handle exception |_ => throw e // rethrow unhandled ex...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#NetRexx
NetRexx
/* NetRexx */ options replace format comments java crossref symbols nobinary   -- ============================================================================= class RExceptions public   -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method test() public signals RExceptions.TakeExcep...
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Joy
Joy
"ls" system.
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Julia
Julia
run(`ls`)
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#K
K
\ls
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#bash
bash
factorial() { if [ $1 -le 1 ] then echo 1 else result=$(factorial $[$1-1]) echo $((result*$1)) fi }  
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Phix
Phix
with javascript_semantics function powir(atom b, integer i) atom res = 1 if i<0 then {b,i} = {1/b,abs(i)} end if while i do if and_bits(i,1) then res *= b end if b *= b i = floor(i/2) end while return res end function ?powir(-3,-5) ?power(-3,-5)
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#ZX_Spectrum_Basic
ZX Spectrum Basic
10 DEF FN i()=((NOT (a OR b))+2*(a AND NOT b)+3*(b AND NOT a)+4*(a AND b)): REM the function can be placed anywhere in the program, but it gets executed faster if it's at the top 20 FOR x=1 TO 20 30 LET a=(x/2)=INT (x/2): REM comparison 1 40 LET b=(x/3)=INT (x/3): REM comparison 2 50 GO TO 50+10*FN i(): REM cases 60 PR...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Slate
Slate
n@(Integer traits) fizzbuzz [ output ::= ((n \\ 3) isZero ifTrue: ['Fizz'] ifFalse: ['']) ; ((n \\ 5) isZero ifTrue: ['Buzz'] ifFalse: ['']). output isEmpty ifTrue: [n printString] ifFalse: [output] ]. 1 to: 100 do: [| :i | inform: i fizzbuzz]
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Wren
Wren
import "/fmt" for Fmt   var primeSieve = Fn.new { |limit| if (limit < 2) return [] var c = [false] * (limit + 1) // composite = true c[0] = true c[1] = true // no need to process the even numbers > 2 var k = 9 while (k <= limit) { c[k] = true k = k + 6 } k = 25 wh...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#Comefrom0x10
Comefrom0x10
pointer_alpha = 1/0 pointer_numeric = 1/0 tape_behind = '' tape_ahead = 1/0 tape_pos = 0 # only for debugging array_behind = 1/0 array_ahead = '' set_tape_ahead = array_ahead array_ahead = 1/0 # shift comefrom if array_ahead is array_ahead cdr = 1/0 cdr = array_ahead shift_tail = cdr new_cell comefrom shi...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#EchoLisp
EchoLisp
  (require 'sequences) (define ALPHABET (list->vector ["A" .. "Z"] )) (vector-push ALPHABET " ")   (define (fitness source target) ;; score >=0, best is 0 (for/sum [(s source)(t target)] (if (= s t) 0 1)))   (define (mutate source rate) (for/string [(s source)] (if (< (random) rate) [ALPHABET (random 27)] s))) ...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#LOLCODE
LOLCODE
  HAI 1.2 HOW DUZ I fibonacci YR N EITHER OF BOTH SAEM N AN 1 AN BOTH SAEM N AN 0 O RLY? YA RLY, FOUND YR 1 NO WAI I HAS A N1 I HAS A N2 N1 R DIFF OF N AN 1 N2 R DIFF OF N AN 2 N1 R fibonacci N1 N2 R fibonacci N2 FOUND YR SUM OF N1 AN N2 OIC IF U SAY SO KTHXBYE  
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Ring
Ring
  # Project : Execute HQ9   bottle("hq9+HqQ+Qq")   func bottle(code) accumulator = 0 for i = 1 to len(code) switch code[i] on "h" see "Hello, world!" + nl on "H" see "hello, world!" + nl on "q" ...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Ruby
Ruby
use std::env;   // HQ9+ requires that '+' increments an accumulator, but it's inaccessible (and thus, unused). #[allow(unused_variables)] fn execute(code: &str) { let mut accumulator = 0;   for c in code.chars() { match c { 'Q' => println!("{}", code), 'H' => println!("Hello, Wor...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#REXX
REXX
/*REXX program executes a Markov algorithm(s) against specified entries. */ parse arg low high . /*allows which ruleset to process. */ if low=='' | low=="," then low=1 /*Not specified? Then use the default.*/ if high=='' | high=="," then high=6 ...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Wren
Wren
var U0 = "U0" var U1 = "U1"   var bazCalled = 0   var baz = Fn.new { bazCalled = bazCalled + 1 Fiber.abort( (bazCalled == 1) ? U0 : U1 ) }   var bar = Fn.new { baz.call() }   var foo = Fn.new { for (i in 1..2) { var f = Fiber.new { bar.call() } f.try() var err = f.error i...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#zkl
zkl
class U0(Exception.Exception){fcn init{Exception.init("U0")}} class U1(Exception.Exception){fcn init{Exception.init("U1")}}   fcn foo{try{bar(U0)}catch(U0){} bar(U1)} fcn bar(e){baz(e)} fcn baz(e){throw(e)} foo()
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Nim
Nim
type SillyError = object of Exception
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Objective-C
Objective-C
@interface MyException : NSException { //Put specific info in here } @end
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Kotlin
Kotlin
// version 1.0.6   import java.util.Scanner   fun main(args: Array<String>) { val proc = Runtime.getRuntime().exec("cmd /C dir") // testing on Windows 10 Scanner(proc.inputStream).use { while (it.hasNextLine()) println(it.nextLine()) } }
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Lang5
Lang5
'ls system
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#BASIC
BASIC
FUNCTION factorial (n AS Integer) AS Integer DIM f AS Integer, i AS Integer f = 1 FOR i = 2 TO n f = f*i NEXT i factorial = f END FUNCTION
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#PicoLisp
PicoLisp
(de ** (X N) # N th power of X (if (ge0 N) (let Y 1 (loop (when (bit? 1 N) (setq Y (* Y X)) ) (T (=0 (setq N (>> 1 N))) Y ) (setq X (* X X)) ) ) 0 ) )
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#PL.2FI
PL/I
declare exp generic (iexp when (fixed, fixed), fexp when (float, fixed) ); iexp: procedure (m, n) returns (fixed binary (31)); declare (m, n) fixed binary (31) nonassignable; declare exp fixed binary (31) initial (m), i fixed binary; if m = 0 & n = 0 then signal error; if n = 0 then return (1); do i...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Small
Small
Integer extend [ fizzbuzz [ | fb | fb := '%<Fizz|>1%<Buzz|>2' % { self \\ 3 == 0. self \\ 5 == 0 }. ^fb isEmpty ifTrue: [ self ] ifFalse: [ fb ] ] ] 1 to: 100 do: [ :i | i fizzbuzz displayNl ]
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Zig
Zig
  const std = @import("std"); const builtin = std.builtin; const heap = std.heap; const mem = std.mem; const meta = std.meta;   fn assertInt(comptime T: type) builtin.TypeInfo.Int { if (@typeInfo(T) != .Int) @compileError("data type must be an integer."); const int = @typeInfo(T).Int; if (int.is_sig...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#Common_Lisp
Common Lisp
  program Execute_Brain;   {$APPTYPE CONSOLE}   uses Winapi.Windows, System.SysUtils;   const DataSize = 1024; // Size of Data segment MaxNest = 1000; // Maximum nesting depth of []   function Readkey: Char; var InputRec: TInputRecord; NumRead: Cardinal; ...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#Elena
Elena
import system'routines; import extensions; import extensions'text;   const string Target = "METHINKS IT IS LIKE A WEASEL"; const string AllowedCharacters = " ABCDEFGHIJKLMNOPQRSTUVWXYZ";   const int C = 100; const real P = 0.05r;   rnd = randomGenerator;   randomChar = AllowedCharacters[rnd.nextInt(AllowedCharacte...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#LSL
LSL
integer Fibonacci(integer n) { if(n<2) { return n; } else { return Fibonacci(n-1)+Fibonacci(n-2); } } default { state_entry() { integer x = 0; for(x=0 ; x<35 ; x++) { llOwnerSay("Fibonacci("+(string)x+")="+(string)Fibonacci(x)); } } }
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Rust
Rust
use std::env;   // HQ9+ requires that '+' increments an accumulator, but it's inaccessible (and thus, unused). #[allow(unused_variables)] fn execute(code: &str) { let mut accumulator = 0;   for c in code.chars() { match c { 'Q' => println!("{}", code), 'H' => println!("Hello, Wor...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Scala
Scala
def hq9plus(code: String) : String = { var out = "" var acc = 0   def bottle(num: Int) : Unit = { if (num > 1) { out += num + " bottles of beer on the wall, " + num + " bottles of beer.\n" out += "Take one down and pass it around, " + (num - 1) + " bottle"   if (n...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Ruby
Ruby
def setup(ruleset) ruleset.each_line.inject([]) do |rules, line| if line =~ /^\s*#/ rules elsif line =~ /^(.+)\s+->\s+(\.?)(.*)$/ rules << [$1, $3, $2 != ""] else raise "Syntax error: #{line}" end end end   def morcov(ruleset, input_data) rules = setup(ruleset) while (matched =...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#OCaml
OCaml
exception My_Exception;; exception Another_Exception of string;;
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Oforth
Oforth
: iwillThrowAnException "A new exception" Exception throw ;   : iwillCatch | e | try: e [ iwillThrowAnException ] when: [ "Exception catched :" . e .cr ] try: e [ 1 2 over last ] when: [ "Exception catched :" . e .cr ] "Done" println ;
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Lasso
Lasso
local( path = file_forceroot, ls = sys_process('/bin/ls', (:'-l', #path)), lswait = #ls -> wait ) '<pre>' #ls -> read '</pre>'
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#LFE
LFE
  > (os:cmd "ls -alrt")  
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#BASIC256
BASIC256
print "enter a number, n = "; input n print string(n) + "! = " + string(factorial(n))   function factorial(n) factorial = 1 if n > 0 then for p = 1 to n factorial *= p next p end if end function
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#PowerShell
PowerShell
function pow($a, [int]$b) { if ($b -eq -1) { return 1/$a } if ($b -eq 0) { return 1 } if ($b -eq 1) { return $a } if ($b -lt 0) { $rec = $true # reciprocal needed $b = -$b }   $result = $a 2..$b | ForEach-Object { $result *= $a }   if ($rec) { return...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Smalltalk
Smalltalk
Integer extend [ fizzbuzz [ | fb | fb := '%<Fizz|>1%<Buzz|>2' % { self \\ 3 == 0. self \\ 5 == 0 }. ^fb isEmpty ifTrue: [ self ] ifFalse: [ fb ] ] ] 1 to: 100 do: [ :i | i fizzbuzz displayNl ]
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#zkl
zkl
// http://stackoverflow.com/revisions/10733621/4   fcn postponed_sieve(){ # postponed sieve, by Will Ness vm.yield(2); vm.yield(3); # original code David Eppstein, vm.yield(5); vm.yield(7); # ActiveState Recipe 2002 D:=Dictionary(); ps:=Utils.Generator(postpone...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#D
D
  program Execute_Brain;   {$APPTYPE CONSOLE}   uses Winapi.Windows, System.SysUtils;   const DataSize = 1024; // Size of Data segment MaxNest = 1000; // Maximum nesting depth of []   function Readkey: Char; var InputRec: TInputRecord; NumRead: Cardinal; ...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#Elixir
Elixir
defmodule Log do def show(offspring,i) do IO.puts "Generation: #{i}, Offspring: #{offspring}" end   def found({target,i}) do IO.puts "#{target} found in #{i} iterations" end end   defmodule Evolution do # char list from A to Z; 32 is the ord value for space. @chars [32 | Enum.to_list(?A..?Z)]   d...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#Lua
Lua
  --calculates the nth fibonacci number. Breaks for negative or non-integer n. function fibs(n) return n < 2 and n or fibs(n - 1) + fibs(n - 2) end  
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Seed7
Seed7
$ include "seed7_05.s7i";   const proc: runCode (in string: code) is func local var char: ch is ' '; var integer: bottles is 0; var integer: accumulator is 0; begin for ch range code do case ch of when {'H'}: writeln("Hello, world!"); when {'Q'}: writeln(code); when {'9...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Sidef
Sidef
class HQ9Interpreter { has pointer; has accumulator;   func bob (beer) { func what { "#{beer ? beer : 'No more'} bottle#{beer-1 ? 's' : ''} of beer" } func where { 'on the wall' } func drink { beer--; "Take one down, pass it around," }   while (beer.is_pos) { [[w...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Rust
Rust
use std::str::FromStr;   #[derive(Clone, Debug)] pub struct Rule { pub pat: String, pub rep: String, pub terminal: bool, }   impl Rule { pub fn new(pat: String, rep: String, terminal: bool) -> Self { Self { pat, rep, terminal } }   pub fn applicable_range(&self, input: impl AsRef<str>) -...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Scala
Scala
import scala.io.Source   object MarkovAlgorithm { val RulePattern = """(.*?)\s+->\s+(\.?)(.*)""".r val CommentPattern = """#.*|\s*""".r   def rule(line: String) = line match { case CommentPattern() => None case RulePattern(pattern, terminal, replacement) => Some(pattern, replacement, terminal == ".") ...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Oz
Oz
raise sillyError end raise slightlyLessSilly(data:42 reason:outOfMemory) end
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#PARI.2FGP
PARI/GP
trap(/* specific error can be given here, or leave blank to catch all */, "caught" , error("bad stuff") )