http://d.puremagic.com/issues/show_bug.cgi?id=1196

           Summary: regression: "cannot alias an expression"
           Product: D
           Version: 1.013
          Platform: PC
        OS/Version: All
            Status: NEW
          Severity: regression
          Priority: P3
         Component: DMD
        AssignedTo: bugzilla@digitalmars.com
        ReportedBy: thomas-dloop@kuehne.cn


This is an interresting case because small - and seemingly unrelated changes - can cause the message to vanish:


# template removeSpace(char[] s, int x = 0) {
#    static if (s[0] == ' '){
#       alias removeSpace!(s[1..$], x+1) removeSpace;
#    }else{
#       alias s removeSpace;
#    }
# }
#
# struct Tuple(A...) {
#    alias A Tuple;
# }

# static assert("Hello you !" == removeSpace!("       Hello you !"));
compile/t/tuple_21_B.d(14): alias dstress.compile.t.tuple_21_B.removeSpace!("
Hello you !",6).removeSpace cannot alias an expression "Hello you !"

# static assert("Hello you !" == removeSpace!("       Hello you !").Tuple[0]);
succeeds

test cases: http://dstress.kuehne.cn/nocompile/t/template_21_A.d http://dstress.kuehne.cn/nocompile/t/template_21_B.d http://dstress.kuehne.cn/run/template_12.d


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http://d.puremagic.com/issues/show_bug.cgi?id=1196


bugzilla@digitalmars.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |INVALID




------- Comment #1 from bugzilla@digitalmars.com  2007-05-08 16:29 -------
Both examples fail when I try it with the same error message. The error message is correct - an alias cannot be made of an expression (in this case, a string literal). A working example would be:

template removeSpace(char[] s, int x = 0)
{
    static if (s[0] == ' '){
       const char[] removeSpace = removeSpace!(s[1..$], x+1);
    }else{
       const char[] removeSpace = s;
    }
}

struct Tuple(A...)
{
    alias A Tuple;
}

static assert("Hello you !" == removeSpace!("       Hello you !"));


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