 | Simple implementation:
class StringFunction_v1:
def __init__(self, expression):
self._f = expression
def __call__(self, x):
return eval(self._f) # evaluate function expression
|
| Problem: eval(string) is slow; should pre-compile expression
class StringFunction_v2:
def __init__(self, expression):
self._f_compiled = compile(expression,
'<string>', 'eval')
def __call__(self, x):
return eval(self._f_compiled)
|
