[Tutor] Verification of variable input

[runsun]

Hi all,

How do I make sure the values been passed into a variable is valid?
For example:

[1] a variable "isBoldface" will take:
     "true", "True", "1", "5" ===> valid
     "false", "fALSE", "0", anyother type ===> invalid

[2] a variable "borderWidth" will take:
     "2", "2.5", 3 ====> valid
     "a", any other type =====> invalid

[3] a variable "align" will take
     "center", "CENTER", "Center", "Left", "right" ... ==> valid
     any other values ===> invalid

I have written two functions for [1] and [2] and both work fine.
Just thinking if there's any builtin function that I can use.

For [1]:

def returnBoolean(b):
        ''' Reutrn 1 if b = "True", "tRue", "TRUE", "1", and any integer
other than 0 .....
            Return 0 if b= 0, 0.00, 5.5, "false", "False", "FALSE", integer
0 ....
        '''
       if type(b)==type(1):            # If b is an integer
                if b!=0: return 1       # anythong other than 0 will set b
to true
        elif type(b)==type("a"):        # if b is a string
                if b.strip().upper()=="TRUE":   return 1
                else return 0

For [2]

def returnInt(x):
        try:
            x=int(x)            #"3", "-4", 3.5, -1 ...
            return x
        except:
            try:
                x=float(x)      #for cases like "3.5"
                return int(x)
            except:
                return 0        # "a", or any other data type

======================================
      ~~ Be like water, be shapeless ~~
Runsun Pan, PhD, Biological Sci. Purdue Univ
Email: runsun@bilbo.bio.purdue.edu
Url : http://bilbo.bio.purdue.edu/~runsun
Tel : 765-496-4186(H), 765-494-4947 (O)
Fax : 775-665-1494 (USA) 094-656-8001 (Taiwan)
        (I can access both through my email)
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