The pattern nothing matches any expressions

[lihebi]

The pattern nothing seems to successfully match any expressions:

@match 1 begin
    nothing => true
    _ => false
end
# => true

@match "hello" begin
    nothing => true
    _ => false
end
# => true

[caseykneale]

Someone in the Julia discord found a similar bug that has a similar smell too it.

g = @match Symbol begin
    String => 1
    Symbol => 2
    _ => 3
end

will give g == 1.
Infact, you can change the type of the first match condition to anything and I believe it will always select the first condition for it's result.

Not sure what's going on in this case, the quick fix I suggested to them was to convert types to symbols and match or if/then on those.

[gafter]

An identifier as a pattern matches any input and binds the input to a variable of that name. nothing and String are just names that can be bound.

If you want to test for the value nothing, use the pattern $nothing.

If you want to test for the type String, use the pattern ::String.