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Str.string_match incorrect
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Date: -- (:)
From: Kurt Welgehausen <kaw@k...>
Subject: Re: [Caml-list] Str.string_match incorrect
> On Tue, Dec 21, 2004 at 11:44:55PM -0800, Evan Martin wrote:
> > This is consistent with the docs, which say:
> >   [string_match r s start] tests whether the characters in s starting at
> >   position start match the regular expression r.
> > and in general with how regular expression systems work. 
>
> Then they're simply wrong. The fundamental operation is
> to check if a string is in a regular set of strings.
> Plainly 'aa' is not in the set { 'a' }.

Str.string_match is almost exactly the same as Python's
re.match:

   # Str.string_match (Str.regexp "a") "ab" 0 ;;
   - : bool = true
   >>> re.match(re.compile("a"), "ab") #succeeds
   <_sre.SRE_Match object at 0x8146f60>

   # Str.string_match (Str.regexp "a") "bab" 0 ;;
   - : bool = false
   >>> re.match(re.compile("a"), "bab") #returns None
   >>>

   # Str.string_match (Str.regexp "a") "bab" 1 ;;
   - : bool = true
   >>> re.match(re.compile("a"), "bab"[1: ])
   <_sre.SRE_Match object at 0x814c748>
   >>> #Python has no parameter to change the start position

Regards