Re: [stack] peg: a lazy, non-deterministic concatenative language

"William Tanksley, Jr" <[email protected]> Tue, 17 Apr 2012 05:26:43 -0700
Newsgroups	gmane.comp.lang.concatenative
Message-ID	<CAFTBfO7wtfg6Haqa=DJ5HEL+7YZzCp-Pb5=eLNm9sAxQTPa64A@mail.gmail.com>
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John Nowak <[email protected]> wrote:
> https://github.com/HackerFoo/peg
> Not mine.

Amazing... This is creative. He's parsing right to left, and executing
only what's needed to evaluate the last word. In cases where
evaluation is ambiguous, he chooses "nondeterministically" (I'm not
sure what that means). If execution fails, he backtracks to a previous
ambiguous point. Words are provided to force failures.

The language uses stack manipulation words, but I'm not sure that it's
actually a stack. Anyone have any discussion on that point?

> - jn

-Wm

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      <p>John Nowak &lt;<a href="mailto:john%40johnnowak.com">[email protected]</a>&gt; wrote:<br>
&gt; <a href="https://github.com/HackerFoo/peg">https://github.com/HackerFoo/peg</a><br>
&gt; Not mine.<br>
<br>
Amazing... This is creative. He's parsing right to left, and executing<br>
only what's needed to evaluate the last word. In cases where<br>
evaluation is ambiguous, he chooses &quot;nondeterministically&quot; (I'm not<br>
sure what that means). If execution fails, he backtracks to a previous<br>
ambiguous point. Words are provided to force failures.<br>
<br>
The language uses stack manipulation words, but I'm not sure that it's<br>
actually a stack. Anyone have any discussion on that point?<br>
<br>
&gt; - jn<br>
<br>
-Wm<br>
</p>

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