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From: Karim <kliateni@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Newbie: Check first two non-whitespace characters
Date: Thu, 31 Dec 2015 19:54:23 +0100
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On 31/12/2015 19:18, otaksoftspamtrap@gmail.com wrote:
> I need to check a string over which I have no control for the first 2 non-white space characters (which should be '[{').
>
> The string would ideally be: '[{...' but could also be something like
> '  [  {  ....'.
>
> Best to use re and how? Something else?

Use pyparsing it is straight forward:

 >>> from pyparsing import Suppress, restOfLine

 >>> mystring = Suppress('[') + Suppress('{') + restOfLine

 >>> result = mystring.parse(' [ { .... I am learning pyparsing' )

 >>> print result.asList()

['.... I am learning pyparsing']

You'll get your string inside the list.

Hope this help see pyparsing doc for in depth study.

Karim