Should find return null when the pattern wasn't found?

[simplepad]

Right now it returns -1, which from what I can see is somewhat of a special case, because in other functions if something could not be found, null is returned. Returning -1 might introduce hidden bugs if the return value is not analyzed, for example:

.string = "foobar"
.index = find!(.string, "123")
.output = slice!(.string, .index)

This code will compile without issues, and the value stored in .output will be "r". Maybe it would be better to return null (which will fail the slice!() function) or make the find!() function fail if the pattern wasn't found, requiring the developer to handle that case explicitly.

[pront]

Hi @simplepad, I took a look at the commit history of find and I didn't find a good reason for returning a -1. I agree null is a better return type to indicate not found. If you (or someone else) is interested in implementing the change, we will need a deprecation first and a diagnostic warning. In the next next version, we can change it and delete the warning.