FIND P'@' PREV 1

Stefan
Administrator

Posts: 990

FIND P'@' PREV 1 Feb 11, 2021 13:39:06 GMT -5

Quote

Post by Stefan on Feb 11, 2021 13:39:06 GMT -5

Observed on version 21026.

I'm having some bother with FIND p'@' PREV 1

This sounds totally daft, but the above command doesn't always find the nearest alphabetic char in column 1.

The actual character in col 1 to be found has no bearing on the matter.

Example: (keep the data and line spacing asis)

                                                                                                    
EnvDecode: PROCEDURE EXPOSE (dbugVars)                                                              
  IF !.DEBUG THEN !.prvL = SIGL                                                                     
  RETURN entry                                                                                      
                                                                                                    
                                                                                                    
KB2GB: PROCEDURE EXPOSE (dbugVars)                                                                  
  IF !.DEBUG THEN !.prvL = SIGL                                                                     
  RETURN entry                                                                                      
                                                                                                    
                                                                                                    
HH_MM_SS: PROCEDURE EXPOSE (dbugVars)                                                               
  IF !.DEBUG THEN !.prvL = SIGL                                                                     
  RETURN entry                                                                                      
                                                                                                    
                                                                                                    
OutTrap: PROCEDURE EXPOSE (gblvars) (dbugVars)                                                      
  IF !.DEBUG THEN !.prvL = SIGL                                                                     
  RETURN resp.0                                                                                     
                                                                                                    
                                                                                                    
ArgDef: PROCEDURE EXPOSE (dbugVars)                                                                 
  IF !.DEBUG THEN !.prvL = SIGL                                                                     
  RETURN def                                                                                        
                                                                                                    
                                                                                                    
GetKeywordArgs: PROCEDURE EXPOSE A. (dbugVars)                                                      
  IF !.DEBUG THEN !.prvL = SIGL                                                                     
  RETURN 0                                                                                          
                                                                                                    
                                                                                                    
GetFolderNames: PROCEDURE EXPOSE (gblvars) (dbugVars)                                               
  IF !.DEBUG THEN !.prvL = SIGL                                                                     
  RETURN 0

1) Cut and paste the above into SPFLITE.

2) Enter FIND p'@' 1 PREV in the command line (do not press <ENTER>)

3) Place the cursor on the last RETURN statement on line 34

4) Hit PF5 (or whatever key you mapped to RFIND)

You should be in on line 32 col 1 'GetFolderNames'

For me it jumps to line 17 col 1 'OutTrap'

5) Repeat the RFIND/PF5

You should be on line 27 col 1 'GetKeywordArgs'
For me it jumps to line 2 col 1 'EnvDecode'

If I keep pressing PF5, I get 'Top of data reached'

Subsequent PF5s do not restart the search from the bottom, or if they do, they do not find anything as the message 'Top of Data reached' remains.

PS: Works fine when going forward (NEXT) but not for reverse (PREV) search

Last Edit: Feb 11, 2021 13:40:12 GMT -5 by Stefan: add version number

George
Administrator

Posts: 4,062

FIND P'@' PREV 1 Feb 11, 2021 15:06:25 GMT -5

Quote

Post by George on Feb 11, 2021 15:06:25 GMT -5

OK, found it. Where else but in our oh-so-simple unified search routine. Just another demonstration of why I'm so reluctant to do ANY kind of change in there. It was calculating the resume search location and when doing a reverse search, it was faulty.

And BTW, when doing a reverse search, regardless of whether you start it with Enter or RFIND, you should not start it with PREV, but with LAST.

George

George
Administrator

Posts: 4,062

FIND P'@' PREV 1 Feb 11, 2021 17:39:39 GMT -5

Quote

Post by George on Feb 11, 2021 17:39:39 GMT -5

No, maybe I wasn't specific.

I was trying to get users to avoid:

Typing a PREV format command and then manually moving the cursor to the last line before pressing Enter. That's what LAST is for. After the first execution, the LAST is basically converted to PREV.

George

Stefan
Administrator

Posts: 990

FIND P'@' PREV 1 Feb 12, 2021 3:16:31 GMT -5

Quote

Post by Stefan on Feb 12, 2021 3:16:31 GMT -5

I'm with Robert. What he does with headers is precisely what I did in my simplified example - looking for function names in which a given statement or variable is used.

In the example, I requested the cursor to be placed on the last line to ensure it generates a repeatable test scenario.

In a scenario where a user is just looking for the previous occurrence of something, relative to the current 'page', finding the LAST occurrence first isn't helpful.

Is the following incorrect?

- Every command which depends on the cursor's location for successful execution, should obtain the current cursor's position at the start of its processing

(and should probably also update the "current position" with the correct data at the end of its execution.)

- Simple keyboard directives like cursor up/down/left/right, etc that don't cause an ATTN event do not maintain the "current position".

- But one of the first things the ATTN event does is to save the cursor position at time of ATTN.

So a reliable value is available when the "FIND xxx PREV" command is initiated, even without a preceding 'FIND xxx LAST' stmt.

- For FIND/CHNAGE, if the search is forward, start at <cursor pos> + 1 else start as <cursor pos> - 1, logically adjusted for line breaks.

Last Edit: Feb 12, 2021 5:56:57 GMT -5 by Stefan

George
Administrator

Posts: 4,062

FIND P'@' PREV 1 Feb 12, 2021 11:47:18 GMT -5

Quote

Post by George on Feb 12, 2021 11:47:18 GMT -5

OK, lets get off the LAST / PREV discussion, I should have kept my mouth shut. I mentioned it only because for me, with Stefan's test scenario, I had to scroll to get the cursor to the end of the file, and I said to myself "Why am I doing this when LAST exists?"

PREV / LAST makes no difference to the problem, any reverse search like that has the problem, regardless of whether PREV or LAST is used. It was a bug, plain, simple and now corrected.

Stefan: Yes, of course all commands need to know the current cursor position, that's basic to nearly every command.

George