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<p><br/><br/>
RETRO has a single dictionary, but does provide a means of using
lexical scope to keep this dictionary clean.
<br/><br/>
<span class="h2">Example</span>
<br/><br/>
<span class='codeblock'><span class="tt">```</span><br/><span class="tt">{{ </span><br/>
<span class="tt">&nbsp;&nbsp;<span class='str'>'A</span> var </span><br/>
<span class="tt">&nbsp;&nbsp;<span class='colon'>:++A</span> &nbsp;<span class='ptr'>&amp;A</span> v:inc <span class='imm'>;</span> </span><br/>
<span class="tt">---reveal--- </span><br/>
<span class="tt">&nbsp;&nbsp;<span class='colon'>:B</span> ++A ++A <span class='fetch'>@A</span> n:put nl <span class='imm'>;</span> </span><br/>
<span class="tt">}} </span><br/>
<span class="tt">```</span></span><br/><br/>
In this example, the lexical namespace is created with <span class="tt">{{</span>. A
variable (<span class="tt">A</span>) and word (<span class="tt">++A</span>) are defined. Then a marker is
set with <span class="tt">---reveal---</span>. Another word (<span class="tt">B</span>) is defined, and the
lexical area is closed with <span class="tt">}}</span>.
<br/><br/>
The headers between <span class="tt">{{</span> and <span class="tt">---reveal---</span> are then hidden from
the dictionary, leaving only the headers between <span class="tt">---reveal---</span>
and <span class="tt">}}</span> exposed.
<br/><br/>
If you wish to hide all headers in a <span class="tt">{{</span> ... <span class="tt">}}</span> block, leave
out the <span class="tt">---reveal---</span>.
<br/><br/>
<span class='codeblock'><span class="tt">```</span><br/><span class="tt">{{ </span><br/>
<span class="tt">&nbsp;&nbsp;<span class='colon'>:a</span> <span class='num'>#3</span> <span class='imm'>;</span> </span><br/>
<span class="tt">&nbsp;&nbsp;<span class='colon'>:b</span> a <span class='prim'>dup</span> <span class='prim'>*</span> <span class='imm'>;</span> </span><br/>
<span class="tt">}} </span><br/>
<span class="tt">```</span></span><br/><br/>
<span class="h2">Notes</span>
<br/><br/>
This only affects word visibility within the scoped area. As an
example:
<br/><br/>
<span class='codeblock'><span class="tt">```</span><br/><span class="tt"><span class='colon'>:a</span> <span class='num'>#1</span> <span class='imm'>;</span> </span><br/>
<span class="tt">&nbsp;</span><br/>
<span class="tt">{{ </span><br/>
<span class="tt">&nbsp;&nbsp;<span class='colon'>:a</span> <span class='num'>#2</span> <span class='imm'>;</span> </span><br/>
<span class="tt">---reveal--- </span><br/>
<span class="tt">&nbsp;&nbsp;<span class='colon'>:b</span> <span class='str'>'a</span> s:evaluate n:put <span class='imm'>;</span> </span><br/>
<span class="tt">}} </span><br/>
<span class="tt">```</span></span><br/><br/>
In this, after <span class="tt">}}</span> closes the area, the <span class="tt">:a #2 ;</span> is hidden and
the <span class="tt">s:evaluate</span> will find the <span class="tt">:a #1 ;</span> when <span class="tt">b</span> is run.
<br/><br/>
<br/><br/>
Use of these words can result in a corrupt dictionary and system
crashes. Specifically, use of <span class="tt">---reveal---</span> with an empty private
or public section will result in dictionary corruption.
<br/><br/>
If you don't need private words, don't put them in a scope. And if
you don't need public words, don't include the <span class="tt">---reveal---</span>.
</p>
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