I recently banged my head on exactly this problem, and tye pointed out that Perl has it own internal routine for deciding whether a scalar is a valid number.

It seems a shame that this internal routine is not exposed to the programmer, and I made an attempt to gain access to it (under AS) using Win32::API to access the internal routine looks_like_number() function in perl56.dll directly. Unfortunately, it proved impossible (for me anyway) to gain access to the address of a scalar in a form that it would accept from within perl. Tye kindly tracked this down to being something to do with it needing a thread-safe verion of the pointer.

I believe that it would be possible to write a small XS module to expose the function, which would make a lot more sense than everyone having to rewrite it's logic using regexs or whatever, but I am not yet ready to go delving into the excesses of XS.

Any takers?

Maybe they will expose it in a later version of Perl. Who knows.

Nah! Your thinking of Simon Templar, originally played by Roger Moore and later by Ian Ogilvy

In reply to Re: Parse float from string by BrowserUk
in thread Parse float from string by gryphon

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