Bug 11921 – dmd doesn't like expressions in templates, only values

I want to parse a substring into an integer. I try: ios7crypt.d: ... string hash = "104306170e120b"; auto seed = parse!(int)(hash[0..2]); ... But dmd complains: ios7crypt.d(68): Error: template std.conv.parse does not match any function template declaration. To get around this, I can separate parsing into two steps. ios7crypt.d: ... string hash = "104306170e120b"; string seed_str = hash[0..2]; auto seed = parse!(int)(seed_str); ... The second snippet compiles and runs. I just wish I didn't have to do this; that the template syntax could handle nested expressions. Full source, in case anyone would like more context: https://github.com/mcandre/ios7crypt/tree/master/d

This is actually because parse() takes a ref source and that slice is an rvalue. I recommend doing this instead: auto seed = hash[0..2].to!int;

As mentioned, this is due to ref, and not a DMD bug. Closing.