| import ast |
| import sys |
|
|
|
|
| class _CatchDisplay: |
| """Class to temporarily catch sys.displayhook""" |
|
|
| def __init__(self): |
| self.output = None |
|
|
| def __enter__(self): |
| self.old_hook = sys.displayhook |
| sys.displayhook = self |
| return self |
|
|
| def __exit__(self, type, value, traceback): |
| sys.displayhook = self.old_hook |
| |
| return False |
|
|
| def __call__(self, output): |
| self.output = output |
|
|
|
|
| def eval_block(code, namespace=None, filename="<string>"): |
| """ |
| Execute a multi-line block of code in the given namespace |
| |
| If the final statement in the code is an expression, return |
| the result of the expression. |
| """ |
| tree = ast.parse(code, filename="<ast>", mode="exec") |
| if namespace is None: |
| namespace = {} |
| catch_display = _CatchDisplay() |
|
|
| if isinstance(tree.body[-1], ast.Expr): |
| to_exec, to_eval = tree.body[:-1], tree.body[-1:] |
| else: |
| to_exec, to_eval = tree.body, [] |
|
|
| for node in to_exec: |
| compiled = compile(ast.Module([node], []), filename=filename, mode="exec") |
| exec(compiled, namespace) |
|
|
| with catch_display: |
| for node in to_eval: |
| compiled = compile( |
| ast.Interactive([node]), filename=filename, mode="single" |
| ) |
| exec(compiled, namespace) |
|
|
| return catch_display.output |
|
|
