How to tell if a string contains valid Python code

Question

If I have a string of Python code, how do I tell if it is valid, i.e., if entered at the Python prompt, it would raise a SyntaxError or not? I thought that using comp

Answer 1

The compiler module is now a built-in.

compile(source, filename, mode[, flags[, dont_inherit]])

Compile the source into a code or AST object. Code objects can be executed by an exec statement or evaluated by a call to eval(). source can either be a string or an AST object. Refer to the ast module documentation for information on how to work with AST objects.

The AST parser is now a seperate module.

ast.parse(expr, filename='<unknown>', mode='exec')

Parse an expression into an AST node. Equivalent to compile(expr, filename, mode, ast.PyCF_ONLY_AST).

Answer 2

Use ast.parse:

import ast
def is_valid_python(code):
   try:
       ast.parse(code)
   except SyntaxError:
       return False
   return True

>>> is_valid_python('1 // 2')
True
>>> is_valid_python('1 /// 2')
False