bearophile wrote:
Walter Bright:
Not a significant issue, as the code to lex it is done, works, and is readily available.

It's not an issue for the compiler, but a modern programming language has to be 
designed for programmers, to be as little bug-prone as possible. Literals as .5 
and 5. are not correct in my natural language, they look ugly, and they are a 
bit dangerous. That's why I think it's better to disallow them.


Translating C code to D.<

The main problem is turning a literal like 0555 into a syntax error, but 
failing silently or giving a different answer.

Now in Python 3+ literals like 0720 are disallowed, you have to use 0o720 
instead. I was one of the people that have suggested and voted for this change. 
It's one of the few changes in Python that come from a suggestion of mine.

Regarding Python 3, it contains a single built-in module that's named 2to3, 
it's not too much long and it's quite useful:
http://docs.python.org/library/2to3.html
I think that writing a similar standard and built-in Python module to translate 
C/H code to D can be positive. Then all D distributions can contain it. Among 
the things it does it to reformat code and convert C octals to D octals :-)

Bye,
bearophile

Just make a CTFE function for converting an octal string to an int.

T octalLiteral(T=int)(string s)
{
   T r=0;
   foreach(c; s) {
     assert(c>='0' && c<='7', "Invalid character in octal literal");
     r *= 8;
     r += (c-'0');
   }
   return r;
}

static assert(octalLiteral("012")==012);
static assert(octalLiteral("0716")==0716);
static assert(octalLiteral!(long)("071625636464")==071625636464L);

Why do we need language support for something which is so obscure and can be so trivially implemented in a library?

(Note that it's only possible because of CTFE).

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