Re: [Pyparsing] How to distinguish a variable from a integer

[Gustavo N. <me...@gu...>]

Bonjour, Denis.

spir said:
> The issue is that your variables can start like a number (the reason why in
> most PLs var names cannot start with a digit). So that: * using (number |
> variable) number masks variable
> * using the opposite number is eaten by variable
>
> You should use the common pattern for a variable, requiring letter or '_'
> at start: variable = Regex("[a-zA-Z_]\w*", re.UNICODE)       (untested with
> unicode) 

Yes, I was aware of that limitation with regular expressions, but I thought 
there was a way to work around that with Pyparsing.

>(also beware that \w includes digits and '_')

Oops, you're right. Thanks!

> so that number and variable are mutually exclusive.
>
> You could also add a lookahead for !(letter | '_') trailing after the
> definition of number, but then your definition of variable is unclear. It
> should be required that a variable has at least one non-digit char. Which
> is uneasy ;-)

Yep, that's not a good solution either.

Well, I'll have to make sure variables don't start with a number. :/

Merci beaucoup!
-- 
Gustavo Narea <xri://=Gustavo>.
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