galope/bit-enum.fs at master · programandala-net/galope · GitHub

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\ galope/bit-enum.fs

\ This file is part of Galope
\ http://programandala.net/en.program.galope.html

\ Author: Marcos Cruz (programandala.net), 2016, 2017.

\ ==============================================================

: bit-enum ( n1 "name" -- n2 )
  dup constant 1 lshift dup 0= -11 and throw ;

  \ doc{
  \
  \ bit-enum ( n1 "name" -- n2 )
  \
  \ Create a constant _name_ with value _n1_. Then get _n2_ by
  \ shifting _n1_ 1 bit to the left. If _n2_ is zero, throw an error
  \ "Result out of range", else return _n2_.
  \
  \ Usage example:
  \
  \ ----

  \ 1
  \ bit-enum first-bit
  \ bit-enum second-bit
  \ bit-enum third-bit
  \ bit-enum fourth-bit
  \ drop

  \ ----
  \
  \ See: `enum`.
  \
  \ }doc

\ ==============================================================
\ Change log

\ 2016-07-11: Write.
\
\ 2017-10-25: Improve documentation.