Bug #1002
Emacs UI: cocoa5-send-line skips too many chars
Description
While trying to understand how cocoa5-send-line works, I discovered that it can skip too far forwards sometimes.
This is probably not serious since no one has reported any such problems, but it should be rectified.
Related issues
History
#1
Updated by John Abbott over 7 years ago
Updated by Here is an example:
-- Line 1 ( 1+2);
Doing "send line" on the first line then moves the cursor to the third line; the open bracket on the second line is skipped over!
#2
Updated by John Abbott over 7 years ago
- Related to Design #998: Emacs UI: sending empty input from cocoa5 buffer added
#3
Updated by John Abbott over 7 years ago
- Status changed from New to In Progress
- % Done changed from 0 to 10
The problem lies in the "mysterious" regexp given to skip-chars-forward.
Currently the regexp is "-*\n-*" but I have no idea where that came from.
I believe it means skip over all - * and any char between \n and * (in the ASCII encoding). To be honest I do not know how it manages to skip over the whitespace that it does skip over.
Anyway, I suggest replacing the regexp with something more comprehensible (or at least add an explanation for what the current regexp means).
#4
Updated by John Abbott over 7 years ago
This leads naturally to the question: which chars do we want to skip over?
At least: Newline, space and tab.Anything else?
Emacs offers char classes in regexps: for instance
[:blank:]matches space and tab[:space:]matches any char with whitespace syntax -- I don't know what that means!
#5
Updated by John Abbott over 7 years ago
- % Done changed from 10 to 20
I think Anna might like to skip over minus signs since she sometimes uses a line of minus signs to separate sections in a demo file... I don't know whether it makes sense to skip over them.
If we do skip minus signs then a file like the following would cause trouble:
3 - 1;
Read as a whole file this is correct input, and produces the result 2 (of course!).
Sent one line at a time, the file is incorrect if the line containing just the minus sign is skipped over!
Similar arguments apply to (forward) slash (which can also be used to introduce comments).
#6
Updated by John Abbott over 7 years ago
The following file will give different results (but no errors) if you read the whole file in one go, or send the file line by line:
len
("()")
;
The point being that with the weird regexp the line containing
("()") is skipped completely.
JAA is feeling ever more convinced that the old regexp is bad.
#7
Updated by John Abbott about 7 years ago
- Status changed from In Progress to Feedback
- Assignee set to John Abbott
- Target version changed from CoCoA-5.?.? to CoCoA-5.2.0 spring 2017
- % Done changed from 20 to 90
- Estimated time set to 2.60 h
I made a change to the regexp a while ago. All the examples in the comments above seem to work in a reasonable way.
#8
Updated by John Abbott almost 7 years ago
- Status changed from Feedback to Closed
- % Done changed from 90 to 100
Closing after 3 months in feedback, and no problems have come up.