I wanted to know How can I convert string to python defined variables.
Basically I want to do this.
if value1 operator value2:
print True
my operator is a string '==' , '>', '<', '!='
so that it becomes
if value1 == value2:
print True
I tried operator = getattr(sys.modules[__name__], operator ) but it work for class.
thanks.
Using the operator module:
import operator
def op(str, value1, value2):
lookup = {'==': operator.eq, '>': operator.gt,
'<': operator.lt, '!=': operator.ne}
if str in lookup:
return lookup[str](value1, value2)
return False
v1 = 1
v2 = 2
print op("!=", v1, v2)
# True
>>> import operator
>>> ops = {'==': operator.eq,
... '>': operator.gt,
... '<': operator.lt,
... '!=': operator.ne}
>>> ops['=='](1,2)
False
>>> ops['=='](2,2)
True
>>> ops['>'](2,2)
False
>>> ops['>'](3,2)
True
>>> ops['!='](3,2)
True
I think you need to explicitly associate your operators with python's:
import operator as op
oper = '==' ## or '<', etc...
value1 = 1
value2 = 2
opdict = {'<': op.lt, '>': op.gt,
'<=': op.le, '>=': op.ge,
'==': op.eq, '!=': op.ne}
if opdict[oper](value1, value2):
print true
if eval(repr(value1) + operator + repr(value2)):
print True
or more simply
print eval(repr(value1) + operator + repr(value2))
Just be careful, eval gets a bad reputation =P
(seriously tho, the solution with the operator module is probably a better choice)
