40 lines
766 B
Forth
40 lines
766 B
Forth
|
# Hiding Words
|
||
|
|
|
||
|
|
It's often useful to be able to hide a word from the global
|
||
|
|
dictionary. This can be done with the lexical scope words,
|
||
|
|
but here I present a different approach.
|
||
|
|
|
||
|
|
To hide a word, it is sufficient to change its name to
|
||
|
|
something that will never be matched. Since strings are
|
||
|
|
null terminated, just replacing the first character with
|
||
|
|
a null suffices.
|
||
|
|
|
||
|
|
So all that needs to be done is to create an array of headers
|
||
|
|
we want to hide, then iterate over that to smudge out the
|
||
|
|
names.
|
||
|
|
|
||
|
|
# Code
|
||
|
|
|
||
|
|
~~~
|
||
|
|
'To-Hide d:create #65 allot
|
||
|
|
|
||
|
|
:private @Dictionary @To-Hide &To-Hide + n:inc store &To-Hide v:inc ;
|
||
|
|
|
||
|
|
:hide-private
|
||
|
|
&To-Hide [ d:name v:off ] a:for-each &To-Hide v:off ;
|
||
|
|
~~~
|
||
|
|
|
||
|
|
# Example
|
||
|
|
|
||
|
|
```
|
||
|
|
:a ;
|
||
|
|
:b ; private
|
||
|
|
:f ; private
|
||
|
|
:c ;
|
||
|
|
:d ; private
|
||
|
|
:e ;
|
||
|
|
|
||
|
|
hide-private
|
||
|
|
```
|
||
|
|
|