eval(expression[, globals[, locals]])
The arguments are a string and optional globals and locals. If provided, globals must be a dictionary. If provided, locals can be any mapping object. Changed in version 2.4: formerly locals was required to be a dictionary.
The expression argument is parsed and evaluated as a Python expression (technically speaking, a condition list) using the globals and locals dictionaries as global and local name space. If the globals dictionary is present and lacks ‘__builtins__’, the current globals are copied into globals before expression is parsed. This means that expression normally has full access to the standard [__builtin__] module and restricted environments are propagated. If the locals dictionary is omitted it defaults to the globals dictionary. If both dictionaries are omitted, the expression is executed in the environment where eval is called. The return value is the result of the evaluated expression. Syntax errors are reported as exceptions. Example:
>>> x = 1 >>> print eval('x+1') 2
This function can also be used to execute arbitrary code objects (such
as those created by compile). In this case pass a code object
instead of a string. The code object must have been compiled passing
'eval' as the kind argument.
Hints: dynamic execution of statements is supported by the exec statement. Execution of statements from a file is supported by the execfile function. The globals and locals functions returns the current global and local dictionary, respectively, which may be useful to pass around for use by eval or execfile.