Type-hinting looks like this:
local var: string = "hello world"
It works with functions too:
local function myfunc(a: string, b: string): number
return tonumber(a) + tonumber(b)
print(myfunc(1, "1")) --> This will emit a warning for argument type mismatch.
There's no effect on performance. This is implemented entirely during the compilation phase.
What types can I use?
void(return type only)
? to indicate nil-able types, e.g.
?string indicates that it may be nil or a string.
You can also use
| to delimit alternatives, e.g.
string|int indicates that it may be a string or an int.
Putting all of this together, we could also have e.g.
?string|int to indicate that it may be nil, a string, or an int.
This is a WIP feature, and it's very difficult to implement in a one-pass compiler. Allow tolerance for missing coverage, and report any bugs.