File size: 3,998 Bytes
6851d40 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 | /*******************************************************************************
* Copyright by the contributors to the Dafny Project
* SPDX-License-Identifier: MIT
*******************************************************************************/
// RUN: %verify "%s"
include "../../src/Wrappers.dfy"
/**
* Implements mutable maps by interfacing with external code, e.g. "MutableMap.java".
*/
module {:extern "DafnyLibraries"} {:options "-functionSyntax:4"} DafnyLibraries {
import opened Wrappers
/**
* NOTE: Only here because of #2500; once resolved import "../../examples/MutableMap/
* MutableMapTrait.dfy".
*/
trait {:termination false} MutableMapTrait<K(==),V(==)> {
function content(): map<K, V>
reads this
method Put(k: K, v: V)
modifies this
ensures this.content() == old(this.content())[k := v]
ensures k in old(this.content()).Keys ==> this.content().Values + {old(this.content())[k]} == old(this.content()).Values + {v}
ensures k !in old(this.content()).Keys ==> this.content().Values == old(this.content()).Values + {v}
function Keys(): (keys: set<K>)
reads this
ensures keys == this.content().Keys
predicate HasKey(k: K)
reads this
ensures HasKey(k) <==> k in this.content().Keys
function Values(): (values: set<V>)
reads this
ensures values == this.content().Values
function Items(): (items: set<(K,V)>)
reads this
ensures items == this.content().Items
ensures items == set k | k in this.content().Keys :: (k, this.content()[k])
function Select(k: K): (v: V)
reads this
requires this.HasKey(k)
ensures v in this.content().Values
ensures this.content()[k] == v
method Remove(k: K)
modifies this
ensures this.content() == old(this.content()) - {k}
ensures k in old(this.content()).Keys ==> this.content().Values + {old(this.content())[k]} == old(this.content()).Values
function Size(): (size: int)
reads this
ensures size == |this.content().Items|
}
class {:extern} MutableMap<K(==),V(==)> extends MutableMapTrait<K,V> {
constructor {:extern} ()
ensures this.content() == map[]
function {:extern} content(): map<K, V>
reads this
method {:extern} Put(k: K, v: V)
modifies this
ensures this.content() == old(this.content())[k := v]
ensures k in old(this.content()).Keys ==> this.content().Values + {old(this.content())[k]} == old(this.content()).Values + {v}
ensures k !in old(this.content()).Keys ==> this.content().Values == old(this.content()).Values + {v}
function {:extern} Keys(): (keys: set<K>)
reads this
ensures keys == this.content().Keys
predicate {:extern} HasKey(k: K)
reads this
ensures HasKey(k) <==> k in this.content().Keys
function {:extern} Values(): (values: set<V>)
reads this
ensures values == this.content().Values
function {:extern} Items(): (items: set<(K,V)>)
reads this
ensures items == this.content().Items
ensures items == set k | k in this.content().Keys :: (k, this.content()[k])
function {:extern} Select(k: K): (v: V)
reads this
requires this.HasKey(k)
ensures v in this.content().Values
ensures this.content()[k] == v
function SelectOpt(k: K): (o: Option<V>)
reads this
ensures o.Some? ==> (this.HasKey(k) && o.value in this.content().Values && this.content()[k] == o.value)
ensures o.None? ==> !this.HasKey(k)
{
if this.HasKey(k) then
Some(this.Select(k))
else
None
}
method {:extern} Remove(k: K)
modifies this
ensures this.content() == old(this.content()) - {k}
ensures k in old(this.content()).Keys ==> this.content().Values + {old(this.content())[k]} == old(this.content()).Values
function {:extern} Size(): (size: int)
reads this
ensures size == |this.content().Items|
}
}
|