Talk:Jump anywhere: Difference between revisions
→Signal use in Rexx: "discussion" gets out of hand
m (→Signal use in Rexx: added comment regarding a choice of: leaving it like that or rephrasing text. -- ~~~~) |
Walterpachl (talk | contribs) (→Signal use in Rexx: "discussion" gets out of hand) |
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: Just exactly what is it that you want to be rephrased in my text (in the REXX example)? I showed an example of a '''signal''' instruction, along with the disclaimer that some REXXes don't allow the example's method of using it (the '''signal''' instruction), although a language specification that says it's legal --- along with the ''exact'' example given in a REXX (Regina) document (I consider Regina REXX to be one of the classic REXXes). As far a what is or isn't the right place to discuss the Regina REXX language documentation, it's a good place as any as we're discussing what's legal as per the '''signal''' instruction in the REXX example shown, and also, most REXX programmers have access that particular document. I used Regina's documentation because it had the example (REXX code) that I used verbatim. I showed a working example of a '''signal''' instruction as per the task description (jump anywhere). I didn't include examples of how it can fail; every instruction can fail in some manner. Most instructions have caveats, exceptions, and ''gotchas''. '''a=a+1''' could produce a result that is unexpected, but that won't stop me from showing how to increment a REXX variable (and not showing a counterexample of possible failures). Also, I don't feel comfortable in pontificating what (REXX) statements should or shouldn't be used for this 'n that and/or under what circumstances, or even judging what (REXX) statements are "bad". Showing a (SIGNAL) failure situation without explaining why the failure occurred isn't a constructive way to warn other programmers. The conditions of why the failure (of the below shown example) occurred should be accompanied with a brief explanation of why that failure is an example of coding an ''illegal'' '''signal''' instruction construct and will cause a '''syntax''' error in REXX. -- [[User:Gerard Schildberger|Gerard Schildberger]] 21:02, 11 December 2012 (UTC)
:: This "discussion" is getting way too scrambled. I try to tell you what I want.
Replace your Regina oriented text at the task with something like this:
"Signal should only be used for very global jumps and condition handling since Signal within or into Do loops, do groups or other control structures may not work as desired" --[[User:Walterpachl|Walterpachl]] 05:03, 12 December 2012 (UTC)
as exemplified by this example:
Example:
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Error 10.1: END has no corresponding DO, LOOP, or SELECT
</pre>
:: why did you explain here what I wanted to demonstrate? and what do you mean by: "There are other uses for the '''signal''' instruction than that."??
--[[User:Walterpachl|Walterpachl]] 05:03, 12 December 2012 (UTC)
: Please note that that your (illegal) code is "executing" the '''END''' instruction which has been rendered invalid by the execution of the '''signal''' instruction, which resulted in the '''syntax''' error (as cautioned in the comments in the REXX section header). -- [[User:Gerard Schildberger|Gerard Schildberger]] 21:02, 9 December 2012 (UTC)
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