From daemon Sat Feb 17 13:14 MEZ 1990
Status: R

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Date: Sat, 17 Feb 90 13:14:09 +0100
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Apparently-To: ertl

>From mcsun!vax1.tcd.ie!trolfs  Sat Feb 17 13:05:02 1990 remote from tuvie
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From: On-Line Information Service <tuvie!vax1.tcd.ie!TROLFS>
Subject: OLIS: CALC file
To: vip!ertl
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Here is an intentional simple infix calculator in Forth:
 
    +----------------------------------------------+
    |   : task ;    variable mode    0 mode !      |
    |                                              |
    |   : calc   mode @  1 =  if  +  exit then     |
    |            mode @  2 =  if  -  exit then     |
    |            mode @  3 =  if  *  exit then     |
    |            mode @  4 =  if  /       then ;   |
    |                                              |
    |   : +   mode @  if calc then  1 mode ! ;     |
    |   : -   mode @  if calc then  2 mode ! ;     |
    |   : *   mode @  if calc then  3 mode ! ;     |
    |   : /   mode @  if calc then  4 mode ! ;     |
    |   : =   mode @  if calc then  0 mode ! ;     |
    |                                              |
    |   \ example:  17 * 2 + 16 / 2 - 17  -->  8   |
    +----------------------------------------------+
 
In order to avoid strange results in your later routines,
please { forget task } after you have run this code.