https://issues.dlang.org/show_bug.cgi?id=12954

          Issue ID: 12954
           Summary: deprecated doesn't work with concatenated strings or
                    anything else but a string literal
           Product: D
           Version: unspecified
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: jmdavisProg@gmx.com

This code:

deprecated("my " ~ "message")
void foo()
{
}

void main()
{
}

gives this error

q.d(1): Error: string expected, not '"my " ~ "message"'

This code gives a similar error:

string bar()
{
    return "my message";
}

deprecated(bar())
void foo()
{
}

void main()
{
}

I would have expected that deprecated would take any arbitrary expression which evaluated to a string at compile time. I'm not sure that it really matters that you can pass it a function (save for consistency with other language features), but the lack of ~ makes it hard to break up lines if you end up with a long deprecation message (and yes, it's generally better to have shorter deprecation messages, but sometimes longer ones are required, and it would be better if they didn't have to be on one, overly long line).

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