Binary literals

[aaronlifton3]

It would be nice if this scalac fork had built-in non-macro binary literals, similar to the macro-based one found in retronym's macrocosm

E.g. https://github.com/retronym/macrocosm/blob/master/src/main/scala/com/github/retronym/macrocosm/Macrocosm.scala#L72

Example:

scala> b"101010"
res4: Int = 42

scala> b"102"
<console>:11: error: exception during macro expansion: invalid binary literal
              b"102"
              ^

[puffnfresh]

What type would it become? Int? Short? Byte? Long? String?

[propensive]

You would want to have some prefix signify the meaning of the subsequent 1s and 0s, and a suffix signify the type, consistent with hex. e.g. 0q1001110100L. Anything else would be quite inconsistent with what we already have.

[non]

I think it could work very similarly to hex literals (0x111).

For example:

0b111Z // Byte
0b111S // Short
0b111  // Int
0b111L // Long

What do you all think?

EDIT: I think this is almost exactly what @propensive is proposing.

[propensive]

It's exactly the same, except I was scared of the possible ambiguity of 0b1011 looking like hex. (Obviously it's not -- it's a mental parsing thing, hence my random suggestion of q.)

[Blaisorblade]

@non's proposal is also coherent with Java 8's binary literals.
👍 on using 0b as a prefix; to consider an alternative, I'd want a mnemonic as good as the one for b.

[som-snytt]

The b mnemonic is weakened by the b boolean conversion in format strings.

To counteract that, add 0k alias for true and 0n0 for false.

0b10 Byte, 0B10 Short, 010 Int, 010L Long, 0cA Char. (No longer fearing the ghost of octal, and no longer wishing to use backslashes for unicode '\u000A'. OK, the pun on 0k loosened me up a bit. Pun on bit unintended.)

[Blaisorblade]

The b mnemonic is weakened by the b boolean conversion in format strings.

Valid point.

@propensive wrote:

Anything else would be quite inconsistent with what we already have.

For instance, this would be inconsistent:

0b10 Byte, 0B10 Short, 010 Int, 010L Long, 0cA Char.

However, I realize I had missed some jokes in your message and I'm unsure about others.

[milessabin]

To resurrect this issue, please rework it as an issue/PR against Lightbend Scala (ie. scala/scala).