Re: pattern matching problem

[Philipp Janda <siffiejoe@...>]

Am 30.08.2013 22:14 schröbte Geoff Smith:
> Hi

Hi!

> I always seem to have difficulty with pattern matching in Lua, here is another example that has stumped me so far
>
> I am trying to trim a number string to remove non significant trailing zeros. So for example
>
> "123.450000000" = "123.45"
> "1234500" = "1234500"
> "12345.00" = "12345.0"
>
> I could of course write a function that iterates through the string from the back dropping zeros, but I thought there is probably a more elegant solution using Lua pattern matching functions.
>
> Can this be done neatly with pattern matching ? Thanks for any suggested code snippets


    local function trim0( s )
      return (string.gsub( s, "^(%d+%.%d?%d-)0*$", "%1" ))
    end

    print( trim0 "123.450000000" )
    print( trim0 "1234500" )
    print( trim0 "12345.0" )

> Regards Geoff

Philipp