Re: sscanf like in Lua

[steve donovan <steve.j.donovan@...>]

2010/8/24 Michal Kolodziejczyk <miko@wp.pl>:
> You probably meant: (%-?%d), because you would be interested in at most
> one minus sign in the front of the number.

The task is sufficiently error-prone to benefit from a custom module:

http://stevedonovan.github.com/Penlight/#T35

"Simple Input Patterns" was my attempt at "Lua String Patterns for
Dummies" (in which category I put myself, most of the time)

> pat = sip.compile '$f / $f'"
> res = {}
> = pat('23 / -20',res)
true
> = res[1],res[2]
23      -20

It brings all the above elements to the party:
 - spaces in the pattern are rendered as %s*
 - $f is replaced by a floating-point number capture pattern
 - any magic characters are escaped
 - $f means that conversion to number must happen

steve d.