doc command doesn't work in try/catch blocks

Hello,

I'm using the try/catch option. When I'm debugging the program and stop at a breakpoint, writing ' doc "function name" ' in the matlab command window causes a crash.

Is it a known bug?

Any way to resolve this issue?

Thanks,

Alex

[Edit: Moved more information from the answers - AU]

After further testing, it seems that the problem is somehow related to the function, but not its name or location. For now I wasn't able to reproduce the bug with other functions.

Below is the error I get:

??? Error: Unexpected MATLAB operator.

Error in ==> isClassMFile at 2 whichComment = regexp(evalc(helpUtils.makeDualCommand('which', fullPath)), '%.*', 'match', 'once');

Error in ==> splitClassInformation>resolveUnaryClass at 423 [isClassMFile, className] = helpUtils.isClassMFile(whichTopic);

Error in ==> splitClassInformation>unaryClassInformation at 401 [classInfo, whichTopic] = resolveUnaryClass(className, justChecking);

Error in ==> splitClassInformation>innerResolveImplicitPath at 128 [classInfo, whichTopic] = unaryClassInformation(objectParts, justChecking);

Error in ==> splitClassInformation>resolveImplicitPath at 104 [classInfo, whichTopic] = innerResolveImplicitPath(topic, implementor, justChecking);

Error in ==> splitClassInformation>innerSplitClassInformation at 44 [classInfo, whichTopic] = resolveImplicitPath(topic, implementor, justChecking);

Error in ==> splitClassInformation at 26 [classInfo, whichTopic, malformed] = innerSplitClassInformation(topic, implementor, justChecking, topicIsDotM);

Error in ==> doc>getClassInformation at 119 classInfo = helpUtils.splitClassInformation(topic, '', true, false);

Error in ==> doc at 88 [docTopic, isMethodOrProp] = getClassInformation(topic);

inside the function 'isClassMFile', first row, the function 'evalc' fails.

the output of: helpUtils.makeDualCommand('which', fullPath) is the line: which('C:\Program Files\MATLAB\R2010a\toolbox\matlab\iofun\sendmail.m')

and remarkably, when the path is the one for the function that causes problem, the output is: which(C:\Program Files\MATLAB\R2010a\toolbox\matlab\iofun\sendmail.m ) - the last comma is on a different line.

Any comment is welcome, Alex

[Oleg Komarov]

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

Answer 1

[Alex Berkovich]

'which' function had a problem because one of the files had a name same as an internal Matlab function.

Answer 2

[Jan]

I cannot confirm this behaviour in Matlab 2009a 32bit, WinXP. Please post the Matlab and OS version you are using. And post an exact copy of the used command - I assume the double quotes are inserted for the posting only. And finally explain, what "crash" means, please. Di you get an error message, a wrong result or a crash dump?

[Paulo Silva]

Jan my code doesn't work, is it a known bug? :)

[Jan]

@Paulo: Yes, it is a none bug. But please define "code" and "my" with more details.

Answer 3

[Sean de Wolski]

try
  error
catch
  doc randi
end

works for for me, R2009b Mac64bit.

Answer 4

[Walter Roberson]

I wonder... what happens if you attempt to "doc" a .m file that has syntax errors? I don't think I've ever tried that.

[Jan]

DOC uses HELP to extract the help text. HELP does not parse the contents of the M-file, but treats it as text file only and crops the initial commented block. Therefore syntax errors do not matter DOC.

But if the function WHICH is overloaded...

[Alex Berkovich]

Do you know what can cause 'which' to be overloaded? thanks.

[Friedrich]

You can overload "which" when you write your own function called "which" which is on the MATLAB path. Maybe try this is ML:

>> which -all which

built-in (C:\Program Files\MATLAB\R2011a\toolbox\matlab\general\which)

C:\Program Files\MATLAB\R2011a\toolbox\simulink\simulink\@dependencies\which.p % dependencies method

>>