bugGNU Octave - Bugs: bug #39009, Dead key sequences incorrectly...


bug #39009: Dead key sequences incorrectly mapped on Windows terminals

Submitted by:  Philip Nienhuis <philipnienhuis>
Submitted on:  Thu 16 May 2013 06:07:40 PM UTC  
Category: InterpreterSeverity: 3 - Normal
Priority: 5 - NormalItem Group: Incorrect Result
Status: FixedAssigned to: None
Originator Name: Philip NienhuisOpen/Closed: Closed
Release: devOperating System: Microsoft Windows

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Wed 02 Oct 2013 01:34:46 PM UTC, comment #8:


This bug has been solved a little while ago - it doesn't happen anymore at least on Octave-3.7.5 and later
Closing this report.

Philip Nienhuis <philipnienhuis>
Project Member
Fri 17 May 2013 03:22:57 PM UTC, comment #7:

I think your use of the term is fine, I was just unfamiliar with it, and it is not really descriptive of what the key is doing. It's not "dead", it is a prefix character.

Anwyay, I don't know how to solve the problem, so someone else will have to provide a solution for this one.

John W. Eaton <jwe>
Project Administrator
Fri 17 May 2013 02:59:59 PM UTC, comment #6:

Sorry, my obviously limited proficiency in English computer lingo gets in the way here.

Wikipedia has the best info I'd guess:

Philip Nienhuis <philipnienhuis>
Project Member
Fri 17 May 2013 02:47:10 PM UTC, comment #5:

What is a "dead key sequence"? How is it generated? How do I tell what keys are in this category?

John W. Eaton <jwe>
Project Administrator
Fri 17 May 2013 02:35:14 PM UTC, comment #4:

It turns out it is the "dead" keys ` ~ ' " ^ that are affected. Or rather: dead key sequences.

I tried a few other keyboard layouts and found one where double quotes weren't a dead key but single quotes were; using that layout the GUI terminal worked OK for the double quotes.

Digging a bit more I see that dead key sequences are incorrectly mapped on all Octave Windows terminals ever since at least Octave-3.2.4 (oldest I have installed), no matter being built with MinGW, MXE, or MSVC.
GUI and CLI both return wrong, but different results for dead key sequences. The fact that dead keys are doubled in the current GUI terminal on Windows looks to be just a more pronounced side effect. Admittedly it's an annoyance rather than a showstopper.
This may have gone unnoticed because one normally doesn't need composed characters in Octave terminals (maybe only in strings). The dead keys ~'"^ weren't in the way as an ensuing space would reveal them.

Intriguingly this is no issue at all on Linux, where I have US Intl keyboard with dead keys as well. I even get the proper Euro symbol with AltGr-5 in the GUI terminal (gets me a question mark in Octave terminals on Windows).

(Title and a few other fields adapted.)

Philip Nienhuis <philipnienhuis>
Project Member
Thu 16 May 2013 09:27:07 PM UTC, comment #3:

I'm not seeing the problem. What font are you using?

I assume this is a recent build? If so, what sources did you use (snapshot version or hg ID)?

My comment about differences was more about how it is not possible to choose defaults for GUI things that make sense for all systems. There are are cultural differences, so one set of defaults or even menu layouts is not likely to seem natural on all systems.

But if multiple characters are inserted for a single key press, it is not intentional. So first we have to find out what is causing it.

John W. Eaton <jwe>
Project Administrator
Thu 16 May 2013 07:30:13 PM UTC, comment #2:

Sorry, I had no intention to do any nitpicking.

What I mean is simply this:
- type one quote in the GUI terminal;
- but you get two consecutive quotes instead of one (with the cursor behind the second one).

That behavior has been there (on my boxes) ever since the first usable GUI on windows.
I've always figured it was meant to aid users inserting quoted strings, but recently I came to the conclusion that it is probably a bug.

I know that Windows and emacs have different cut-'n-paste key sequences (and I've for a long time used OS/2 where it was again different); but I fail to see how fixing this "bug" would annoy many people.

Anyway, I'm sorry to have upset you.

Hmmm I wonder if it could be related to my keyboard settings (US Int'l with dead keys), but that's also the setting on my Linux boxes where it behaves OK.

Philip Nienhuis <philipnienhuis>
Project Member
Thu 16 May 2013 06:24:40 PM UTC, comment #1:

Can you explain what you mean by "consistently automatically repeated"? Precisely how do I reproduce the problem you are seeing? Typing a single or double quote seems to insert normally for me.

As for differences in behavior on different systems, you'll upset just as many people (if not more) if you force one style of keybindings (for example) on everyone. Windows users want C-c C-v to cut and paste. I'd rather have Emacs readline bindings. So the long term goal would be to allow all of these things to be customized and to actually work.

We know there are many problems now. Nit picking at this stage is not super helpful.

John W. Eaton <jwe>
Project Administrator
Thu 16 May 2013 06:07:40 PM UTC, original submission:

In the Windows terminal, quotes (and double quotes) are consistently automatically repeated and the cursor is positioned after the repeated quote.

I'd rather get rid of this because:

1. I use Octave on both Windows and Linux systems, sometimes simultaneously, and different behavior on different OSes gets very distracting.

2. Even if this behavior is to remain, the cursor should be positioned before the second quote, not after it.

Philip Nienhuis <philipnienhuis>
Project Member


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    Follow 5 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Wed 02 Oct 2013 01:34:46 PM UTCphilipnienhuisStatusNone=>Fixed
    Fri 17 May 2013 02:35:14 PM UTCphilipnienhuisCategoryGUI=>Interpreter
      Item GroupNone=>Incorrect Result
      SummaryGUI: Quotes always repeated in Windows terminal=>Dead key sequences incorrectly mapped on Windows terminals

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