Re: Underscore in binary literals

Hi Rahul, Thanks for the explanation. Hmm, Is not there much need... Thank you code example. I will also look at lexer for my study [1]. [1]: https://phabricator.haskell.org/D22 Thank you :) , Takenobu 2017-09-26 21:58 GMT+09:00 Rahul Muttineni :

Implementation-wise, it's no so difficult to include - the lexer needs to be tweaked. But it seems like a specialised use-case that will only affect a minority of users is probably not worthwhile as an extension to the language/compiler.

Maybe you can try using OverloadedStrings and implement this as a library?

``` newtype Binary = Binary Integer deriving Num

instance IsString Binary where fromString binaryLiteral = error "Code here to parse binary literal with underscores"

binaryVal :: Binary binaryVal = "1101_1110_0101" ```

Hope that helps, Rahul

On Tue, Sep 26, 2017 at 8:40 AM, Takenobu Tani wrote:

...

Dear devs,

GHC's BinaryLiterals extension is useful. (For example, x = 0b110111000101)

Is it difficult to include underscore(_) in the format like Verilog-HDL[1] ? (For example, x = 0b1101_1100_0101)

[1]: https://inst.eecs.berkeley.edu/~cs150/fa06/Labs/verilog-ieee .pdf#page=20

Regards, Takenobu

_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs

-- Rahul Muttineni