Refused purity conversion of immutable array of arrays

[dlangBugzillaToGithub]

bearophile_hugs reported this on 2014-05-29T12:30:31Z

Transferred from https://issues.dlang.org/show_bug.cgi?id=12819

Description

I am not sure, but perhaps both functions should compile:


immutable(string)[] foo() pure {
    char[][] a;
    return a; // OK
}
string[] bar() pure {
    char[][] b;
    return b; // Error
}
void main() {}


DMD 2.066alpha gives:

test.d(7,12): Error: cannot implicitly convert expression (b) of type char[][] to string[]