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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: REQ: Expression parser
Date: 1998/01/22
Message-ID: <dewar.885449293@merv>#1/1
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Date: 1998-01-22T00:00:00+00:00
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dagoon asks

<<Hello, I just started coding in ada, so I have problems, esp. with string
handling since it's much different from C or pascal style... I'd love to
see an example of expression parser (like getting "2+2" string and giving
integer=4). I also know that string in ada is saved as (first,last,*text)
but I don't know if there's any simply method of changing first and last.
thanks for any help, regards
>>

Have a look at Ada.Strings.Unbounded, and no a string in Ada is not
"saved as first,last,*text", it is a more abstract object as you
will see from this specification.

If you want to see some extensive examples of the use of this abstraction,
have a look at the coding of GNAT.Spitbol.Patterns in the GNAT library.