Path: csiph.com!news.mixmin.net!newsreader4.netcologne.de!news.netcologne.de!fu-berlin.de!uni-berlin.de!not-for-mail From: Karim Newsgroups: comp.lang.python Subject: Re: Newbie: Check first two non-whitespace characters Date: Fri, 1 Jan 2016 10:43:39 +0100 Lines: 43 Message-ID: References: <240ab049-68a0-4a00-b911-d58cae9bfbcf@googlegroups.com> <568579DF.50805@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Trace: news.uni-berlin.de k0mDw1ZmaTfUWoT3T+ysIgiYaPnbkD40ymRsh6ygOMTg== Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.051 X-Spam-Evidence: '*H*': 0.90; '*S*': 0.00; 'ideally': 0.04; 'subject:two': 0.07; 'subject:characters': 0.09; 'build.': 0.16; 'forward:': 0.16; 'received:192.168.43': 0.16; 'received:io': 0.16; 'received:psf.io': 0.16; 'subject:non': 0.16; 'wrote:': 0.16; 'string': 0.17; '>>>': 0.20; 'to:2**1': 0.21; 'doc': 0.22; 'lawrence': 0.22; 'parser': 0.22; 'import': 0.24; 'header:In- Reply-To:1': 0.24; "i've": 0.25; 'header:User-Agent:1': 0.26; '(which': 0.26; 'be:': 0.29; 'depth': 0.29; 'pile': 0.29; 'print': 0.30; 'message-id:@gmail.com': 0.34; 'received:google.com': 0.35; 'could': 0.35; 'something': 0.35; 'received:74.125.82': 0.35; 'but': 0.36; 'should': 0.36; 'tool': 0.36; 'to:addr:python-list': 0.36; 'subject:: ': 0.37; 'list.': 0.37; 'received:192': 0.39; 'subject:-': 0.39; 'to:addr:python.org': 0.40; 'mark': 0.40; 'space': 0.40; 'ever': 0.60; 'your': 0.60; "you'll": 0.61; 'hope': 0.61; 'email addr:gmail.com': 0.62; 'charset:windows-1252': 0.62; 'introduction': 0.63; 'more': 0.63; 'intent': 0.66; 'received:74.125.82.47': 0.84; 'seen.': 0.84; 'to:addr:yahoo.co.uk': 0.84; 'subject:Check': 0.95 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-type:content-transfer-encoding; bh=fRxfzWW447mukiFnjgjfDSdZBIcXGyHbjBm4b9vfCPw=; b=TJMseuvLqH1mf82Oc7TtX1PS8wVjwzYqUMv3lRuvTs0fM+TfU1u/pxBRJIg06uYXog 1FgnGvLBXOuewUCZgoEqQOOouk3NSOnEJb1pTtRVwc/FVjLB5pyKLMlZCijnCC8A6ctE eNAciWGkWWVqzWT0dJ+VpWMR3GwyklIX0V9UpHVHk6DIgolyDXPs30dCOJm7lZqipDVx RXtmPRBkpoBTN3kLhzAex3WeNWMKVb42Kxc6bUUIfhgZQYCmn//3q6iCW5Psu2WU4lzv IGs+Gs+iKchBwUovj+Dm7rB+JOOi1LPH00BtRhR6A9NkpnsXAr/hMlqilq059XLWUOX/ tttQ== X-Received: by 10.28.221.85 with SMTP id u82mr73955370wmg.95.1451641421048; Fri, 01 Jan 2016 01:43:41 -0800 (PST) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 In-Reply-To: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.20+ Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com comp.lang.python:101101 On 01/01/2016 00:25, Mark Lawrence wrote: > On 31/12/2015 18:54, Karim wrote: >> >> >> 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 > > Congratulations for writing up one of the most overengineered pile of > cobblers I've ever seen. > You welcome ! The intent was to make a simple introduction to pyparsing which is a powerful tool for more complex parser build. Karim