Difference between revisions of "LSL Protocol/ListMessage"

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m (clarify - type out many more of the missing words)
m (tweak to say 0 results, 1 result, or 2+N results representing a list of N results is the normal case, with the arbitrarily reserved <> result being the non-result of a meaningless verb)
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<pre>
<pre>
[] = unknown verb
[ ] = the result of a verb that returns no result
 
[ "<>" ] = the result of a verb that returns no result


[ 0... ] = float or integer result
[ 0... ] = float or integer result
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[ "<...>" ] = rot or vector
[ "<...>" ] = rot or vector


[ "[", ..., "]" ] = list, may be empty
[ "[" "]" ] = empty list
[ "[", ..., "]" ] = non-empty list
 
[ verb "(", ..., ")" ] = verb applied to evaluated args = verb and list of zero or more args, maybe nested in the sense of args may be lists


[ "(", ..., ")" ] = partially evaluated Polish expression = list of verb with zero or more args, may be nested in the sense of args may be lists
["<>"] = the non-result of a meaningless verb
</pre>
</pre>

Revision as of 20:59, 14 October 2007

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List Message Protocol

(Proposed) (Draft, not implemented) (Open for comments)

When we solve problems like interpreting an LSL expression a la Chatbot, ...

We then work with results of any non-list type, also results of list type, also parameter lists that include lists as entries, also the results of verbs that return no results, also the result that is failing to make sense of an unintelligible unknown verb.

I guess we want llMessageLinked to pass such interpreter things to link_message, so that we can divide the work of interpretation across indefinitely many scripts.

I guess we want to invent some way of escaping interpreter things, in three parts:

i) some way of losslessly encoding any string as a string without troublesome punctuation that makes the one string look like more strings, and

ii) some way of losslessly encoding any list as a string, and

iii) some way of losslessly encoding interpreter things as a list.

Answers for that dream include:

i) A scheme for losslessly encoding any string as a string that begins with "\"" and contains no troublesome punctuation may be "\"" + llEscapeURL(string) + "\"".

ii) A scheme for losslessly encoding any list as a string may be to encode its strings and then llDumpList2String with a ", " separator.

iii) A scheme for losslessly encoding interpreter things (without source comments) as a list may be:

[ ] = the result of a verb that returns no result

[ 0... ] = float or integer result
[ "\"...\"" ] = key or string result, may be empty
[ "<...>" ] = rot or vector

[ "[" "]" ] = empty list
[ "[", ..., "]" ] = non-empty list

[ verb "(", ..., ")" ] = verb applied to evaluated args = verb and list of zero or more args, maybe nested in the sense of args may be lists

["<>"] = the non-result of a meaningless verb