-- FORTH-83 SYSTEM EXTENSION WORD SET
Copyright (C) Tektronix, Inc. 1998 - 2001. All rights reserved.
description: forth-83 did define a system extension word set which was deleted in dpans94 due to some problems with the native-compiling variants of forth. pfe is traditional enough to use the words as they were originally intended.
FORTH
<MARK
( -- DP-mark )compile-only( | ); |
| ; |
memorizes the current DP on the CS-STACK used for <RESOLVE later. Useful for creation of compiling words, eg. BEGIN , see AHEAD
simulate: : <MARK ?COMP HERE ;
FORTH
<RESOLVE
( DP-mark -- )compile-only( | ); |
| ; |
resolves a previous <MARK , actually pushes the DP-address memorized at <MARK into the dictionary. Mostly used after BRANCH or ?BRANCH in compiling words like UNTIL
simulate: : <RESOLVE ?COMP , ;
FORTH
MARK>
( -- DP-mark )compile-only( | ); |
| ; |
makes room for a pointer in the dictionary to be resolved through RESOLVE> and does therefore memorize that cell's address on the CS-STACK Mostly used after BRANCH or ?BRANCH in compiling words like IF or ELSE
simulate: : MARK> ?COMP HERE 0 , ;
FORTH
RESOLVE>
( DP-mark -- )compile-only( | ); |
| ; |
resolves a pointer created by MARK> Mostly used in compiling words like THEN
simulate: : RESOLVE> ?COMP HERE SWAP ! ;
FORTH
BRANCH
( .. )();
as:"branch";
ordinary primitive BRANCH
an executable word (no special usage info)
or wrapper call around p4_else_execution
FORTH
?BRANCH
( .. )();
as:"question-branch";
ordinary primitive ?BRANCH
an executable word (no special usage info)
or wrapper call around p4_if_execution
FORTH
CONTEXT
( .. )();
as:"context";
- loader type P4_DVaL CONTEXT
context (no special usage info)
FORTH
CURRENT
( .. )();
as:"current";
threadstate variable CURRENT
current (no special usage info)
ENVIRONMENT
SYSTEM-EXT
( .. )();
as:"system-minus-ext";
( 1983 ) constant SYSTEM-EXT
an ordinary constant (no special usage info)