locate throws error

[MaxSagebaum]

A string.locate which does not find the string to locate throws an error in gsl e.g.:

create.gsl

.ignorecase = 0 
echo string.locate("Test", "Te")
echo string.locate("Test", "Ta")

The output is:

> gsl create    
GSL/4.1.4 Copyright (c) 1996-2016 iMatix Corporation
gsl/4 I: Processing create...
gsl/4 M: 0
(create.gsl 3) Undefined expression: string.locate (...)

Is there an option to catch this error or to return -1 instead?
The error message is also not very helpful. It should be something like:

(create.gsl 3) Could not locate 'Ta' in 'Test'.

[MaxSagebaum]

One possible patch would be:

https://gist.github.com/MaxSagebaum/a502d0fe5e5e8babe05761d3a62a7514#file-0001-string-locate-and-string-locate_last-return-1-if-nee-patch

[jschultz]

The behaviour you observe is by design. That is, if the substring is not found string.locate returns an undefined value. If you want your code to handle such a case, you would do something like:

echo string.locate("Test", "Ta") ? "UNDEFINED"

or if you want to assign the (undefined) result to a variable

res = string.locate("Test", "Ta") ?

[MaxSagebaum]

Ok, that makes sense. Thank you for the explanation.