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Comment by WalterBright | Hacker News Reader

He missed one important thing - the C preprocessor is completely unaware of C types. Its expressions follow different rules.

A major goal of D was to make the language expressive enough to not leave room for the preprocessor:

1. modules

2. manifest constants

3. nested functions

4. lambdas

5. static if

6. compile time function execution

7. string mixins

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I don't think he did miss that, rather it simply wasn't on-topic for the article he was writing. Anybody who has used the C preprocessor knows it works at the level of text/tokens and no further. The fact that it knows nothing of types would hardly be "scandalous"

But you can go ahead and use this thread to promote D anyways.

The #if does more than just text and tokens, it has an expression grammar (constant-expression). It's implementation-defined whether the following two produce the same value:

    #if 'z' - 'a' == 25
    if ('z' - 'a' == 25)

Another difference is all constants are typed as intmax_t and uintmax_t, not the usual C types. Yes, it does have types.

This difference in behavior from C expressions is not necessary.

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