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Pragmas has given me a powerful hook into the Compiler/Parser complex.
I may be misusing them, but my experiment worked and gave me the
insights I needed into the relationships between static and dynamic
variables.<br>
<br>
A small and simple extension to the Parser made it generate in-line
code for special pragmas. (Thanks to Klaus for helping me with this).
An example method:<br>
<blockquote><b>animateStars </b><br>
" Add and remove stars randomly, trying to keep total number of
stars = 'numberOfStars' "<br>
<Role: <i>#<b>Collab</b>> </i><Role: <i>#<b>StarsCount</b>></i><br>
[maestro currentState == #STARS] whileTrue:<br>
<i>[<b>Collab </b></i>refresh.<br>
<i><b>StarsCount </b></i>>= maxNumberOfStars ifTrue: [self
deleteStar].<br>
<i><b>StarsCount </b></i><= maxNumberOfStars ifTrue: [self
placeStar]]<br>
</blockquote>
The Parser extends role variable names such as <i><b>StarsCount </b></i>into<br>
<blockquote>self playerForRole: <i>#<b>StarsCount</b></i><br>
</blockquote>
which looks up the binding for <i>#<b>StarsCount </b></i>in a dynamic
name space. (The name space object lives on the stack)<br>
<br>
This was just a step in a larger experiment; more later.<br>
--Trygve<br>
<br>
On 19.03.2008 14:57, itsme213 wrote:
<blockquote cite="mid:frr64s$g7s$1@ger.gmane.org" type="cite">
<pre wrap="">"Ramon Leon" <a class="moz-txt-link-rfc2396E" href="mailto:ramon.leon@allresnet.com"><ramon.leon@allresnet.com></a> wrote in message
</pre>
<blockquote type="cite">
<pre wrap="">Pragmas are static and aren't nearly as flexible as
Magritte descriptors, which are real objects and don't face the
limitations
of pragmas.
</pre>
</blockquote>
<pre wrap=""><!---->
Perhaps it need not be either-or? e.g. The pragma could be evaluated to
record the "static" descriptions on the classes as any kind of real objects,
including Magritte-like Descriptions:
Foo>>x
<setUpMeta: #bar>
PragmaInterpreter>>setUpMeta: aSymbol for: aClass
aClass recordMeta: aSymbol
And there could still be instance-level access from objects, which by
default just uses the "static" descriptions that PragmaInterpreter recorded
on the classes, but has a hook for dynamic (instance-specific) behavior:
Object>>getMeta: aSymbol
(self class getMeta: aSymbol)
overridenBy: (self dynamicGetMeta: aSymbol)
Just a thought.
- Sophie
</pre>
</blockquote>
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<p class="MsoNormal" style=""><span class="SpellE"><span
style="font-size: 10pt; font-family: Arial;" lang="EN-GB">Trygve</span></span><span
style="font-size: 10pt; font-family: Arial;" lang="EN-GB">
Reenskaug<span style=""> </span>mailto: <span class="SpellE"><a class="moz-txt-link-abbreviated" href="mailto:trygver@ifi.uio.no">trygver@ifi.uio.no</a></span></span><span
style="font-size: 10pt; font-family: Arial;"><o:p></o:p></span></p>
<p class="MsoNormal" style=""><span class="SpellE"><span class="GramE"><span
style="font-size: 10pt; font-family: Arial;" lang="EN-GB">Morgedalsvn</span></span></span><span
class="GramE"><span style="font-size: 10pt; font-family: Arial;"
lang="EN-GB">.</span></span><span
style="font-size: 10pt; font-family: Arial;" lang="EN-GB"> 5A <span
style=""> </span><a class="moz-txt-link-freetext" href="http://heim.ifi.uio.no/~trygver">http://heim.ifi.uio.no/~trygver</a><o:p></o:p></span></p>
<p class="MsoNormal" style=""><span
style="font-size: 10pt; font-family: Arial;">N-0378
Oslo<span style=""> </span>Tel: (+47) 22 49 57 27<o:p></o:p></span></p>
<p class="MsoNormal" style=""><span class="SpellE"><span
style="font-size: 10pt; font-family: Arial;">Norway</span></span><span
style="font-size: 10pt; font-family: Arial;"><o:p></o:p></span></p>
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