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SMLFamily / Successor-ML

A version of the 1997 SML definition with corrections and some proposed Successor ML features added.
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Integer/Word constants within string constants #26

Open ratmice opened 8 years ago

ratmice commented 8 years ago

It would be nice if in addition to the decimal constant \ddd and \uxxxx you could just embed an integer constant directly into a string constant prepended by \e.g. #"\0x33" or something similar to the c syntax '\x33'

The Char.chr function works for this, but it cannot be used in pattern matches

[edit: I suppose just embedding the integer/word constants isn't terribly elegant due to \1x33 etc]

JohnReppy commented 8 years ago

You already have decimal integer constants embedded in strings with "\ddd"; are you asking for 2-byte hexadecimal constants too?

ratmice commented 8 years ago

Yeah, It isn't terribly important as you mention I can (and currently do use "\ddd"), basically the same thing that dwrensha did here:

https://github.com/dwrensha/robotrevolutiondance/blob/master/sml-lib/files/elf/elf.sml The elf specification defines this by its hex constant: www.sco.com/developers/gabi/latest/ch4.eheader.html ELFMAG0 0x7f e_ident[EI_MAG0]

sometimes it would be nice to reflect the constant as defined, rather than doing the conversion, for the benefit of readers comparing the implementation and specification.