mirror of
https://git.sr.ht/~crc_/retroforth
synced 2024-11-16 19:48:56 +01:00
159 lines
3.4 KiB
Text
159 lines
3.4 KiB
Text
# Dictionary: Word Used In ...
|
|
|
|
Given a word `w0` , I wish to know all words that uses `w0`.
|
|
To that end, first I need to know whether a word `w1` uses
|
|
`w0` or not.
|
|
|
|
There are two candidate cell patterns for `w0` usage in `w1`.
|
|
These are:
|
|
|
|
`'lica.... i` or `LIteral CAll 0 0` in nga.
|
|
`'lica.... i` in nga is #2049.
|
|
|
|
~~~
|
|
#2049 'LICA.... const (LIteral_CAll_0_0_instruction
|
|
:lica....? (n-f) LICA.... eq? ;
|
|
~~~
|
|
|
|
`'liju.... i` or `LIteral JUmp 0 0` in nga.
|
|
`'liju.... i` in nga is #1793.
|
|
|
|
~~~
|
|
#1793 'LIJU.... const (LIteral_JUmp_0_0_instruction
|
|
:liju....? (n-f) LIJU.... eq? ;
|
|
~~~
|
|
|
|
The `pattern?` word will check for both.
|
|
|
|
~~~
|
|
:pattern? [ lica....? ] [ liju....? ] bi or ;
|
|
~~~
|
|
|
|
If pattern is followed by `w0`'s execution token `xt0`,
|
|
then `w1` uses `w0`.
|
|
|
|
The pattern of two cells to be sought is
|
|
|
|
LICA.... (or LIJU....)
|
|
xt0
|
|
|
|
The name of `w1` may be found by `'a1 d:lookup d:name`
|
|
in which `a1` is `w1`'s address.
|
|
|
|
Variables `Used` contains `a0` and `In` contains `a1`.
|
|
Make sure the word's class is `class:word` and not something
|
|
else, like `class:primitive`, `class:data`, etc.
|
|
|
|
~~~
|
|
'Used var (a0
|
|
'In var (a1
|
|
:class:word? (a-f) d:class fetch &class:word eq? ;
|
|
:used (a-) dup !Used ;
|
|
:in (a-) dup !In ;
|
|
~~~
|
|
|
|
Set the code range to search for the pattern.
|
|
|
|
~~~
|
|
'Start var
|
|
'End var
|
|
~~~
|
|
|
|
The start is the execution token.
|
|
|
|
~~~
|
|
:start (-) @In d:xt !Start ;
|
|
~~~
|
|
|
|
The end is two cells before the first newer entry to the
|
|
dictionary.
|
|
|
|
If that cell is not `lica...`, then the next cell does not
|
|
hold an execution token.
|
|
|
|
The first newer entry may be found by `d:new fetch` .
|
|
|
|
~~~
|
|
:d:new-old (a-aa)_returns_(This_0)_if_This_is_d:last
|
|
d:last dup-pair eq? (this_last_flag
|
|
[ drop #0 ] if; (exit_if_this_is_last (this_last
|
|
[ dup-pair d:link fetch (this_newer_this_new
|
|
eq? [ TRUE ] [ d:link fetch FALSE ] choose (this_newer_flag
|
|
] until (this_newer
|
|
swap d:link fetch ; (newer_old
|
|
|
|
:d:new (a-a) d:new-old drop ;
|
|
|
|
:end (-) @In d:new dup n:zero?
|
|
[ here #2 - ] [ dup #2 - n:max ] choose !End ;
|
|
~~~
|
|
|
|
Check if a pair of cells indicates that the word is used.
|
|
|
|
~~~
|
|
:pair? (a-f) dup fetch pattern?
|
|
[ #1 + fetch @Used d:xt fetch eq? ] [ drop FALSE ] choose ;
|
|
~~~
|
|
|
|
~~~
|
|
'Address var (head_address_of_the_pair_being_checked
|
|
'More var (TRUE_=_there_are_remaining_pairs_to_check
|
|
'Found var (TRUE_=_@In_used_@Used
|
|
:more (-) @Address @End lt? [ TRUE ] [ FALSE ] choose !More ;
|
|
:prepare (-) start end @Start !Address FALSE !Found more ;
|
|
|
|
:uses? (-f)_does_@In_use_@Used_?
|
|
prepare [
|
|
(pair-found @Address pair? [ &Found v:on ] if )
|
|
(more-to-check more &Address v:inc )
|
|
(condition-to-loop @Found not @More and ) ] while @Found ;
|
|
~~~
|
|
|
|
```
|
|
:t (aa-) used in start end ;
|
|
:a 'a s:put ;
|
|
:b a 'b s:put ;
|
|
:c b 'c s:put ;
|
|
'b d:lookup in 'a d:lookup used
|
|
uses? n:put nl
|
|
```
|
|
|
|
Final product.
|
|
|
|
~~~
|
|
:used-in (a-)
|
|
used
|
|
[ dup class:word?
|
|
[ in uses? [ @In d:name s:put sp ] if drop ] [ drop ] choose
|
|
] d:for-each drop ;
|
|
:d:used-in (s-) d:lookup used-in ;
|
|
~~~
|
|
|
|
```
|
|
'a d:lookup used-in
|
|
```
|
|
|
|
Hide unnecessary words.
|
|
|
|
~~~
|
|
'LICA.... d:lookup d:link fetch
|
|
'd:used-in d:lookup d:link store
|
|
~~~~
|
|
|
|
# Limitations
|
|
|
|
This only searches visible words. Any headers that are hidden
|
|
from the dictionary are no longer visible. So:
|
|
|
|
:foo dup * + ;
|
|
|
|
{{
|
|
:test #2 #3 foo ;
|
|
----reveal--
|
|
:bar test n:put nl ;
|
|
}}
|
|
|
|
'foo d:used-in
|
|
|
|
This will not see the use of `foo` in `test` as the header for
|
|
`test` is not visible after the closing `}}`.
|