Mia unua programo en Forth

[ca] A veure si sabeu què fa el programa.

[eo] Jen. Mi uzis iom da gforth-aj aferoj, jes. Provu diveni, kion la programo faras.

#! /usr/bin/gforth

create stat-array 256 cells allot

4000 constant buffersize
create cbuffer buffersize chars allot

: count-char ( c -- )  \ Updates the stat-array according to the new character read
  cells stat-array + 1 swap +! ;

: read-chars ( -- u2 wior ) \ read chars from the file, and put them into cbuffer
  cbuffer buffersize stdin read-file ;

: clear-stat ( -- ) \ resets the char statistics to 0 for each char
  stat-array 
  256 0 do
    dup 0 swap !
    1 cells +
  loop
  drop ;

: count-chars ( n -- ) \ counts the given amount of chars from the cbuffer
  cbuffer swap 0 do
     dup c@ count-char
    1 chars +
  loop drop ;

: eat-file ( -- ) \ reads chars from a file, and counts them
  begin
    read-chars over swap 0= swap 0> and while
    count-chars
  repeat ;

: show-char ( c -- ) \ shows a character if printable, and outputs its ascii value in []
  dup dup 32 > swap 127 < and if
    dup emit space else 2 spaces then
  [char] [ emit 3 .r [char] ] emit space ;

: show-results ( -- ) \ shows the results of characters counted
  stat-array 
  256 0 do
    dup @ dup 0 if 
    s" Char " type
    i show-char
    s" has occurrences: " type
    . cr
    else drop
    then
    1 cells +
  loop ;

: get-stat ( -- ) \ counts the statistics in stdin, and shows the results.
  clear-stat eat-file show-results ;

get-stat bye