I changed the already_existed variable name to delete_fcn since it seemed clearer.  I checked in the changeset here http://hg.savannah.gnu.org/hgweb/octave/rev/4c080cbc4ef9.

The issue with having to type dbcont twice is because the isdir script is called when print_usage() is invoked.  See the transcript below where I set a breakpoint in isdir ("dbstop isdir") before proceeding with another breakpoint and dbcont.

octave:2> dbstop poly
ans =  57
octave:3> poly
stopped in /home/rik/local/share/octave/4.1.0+/m/polynomial/poly.m at line 57
57:   if (nargin != 1)
debug> dbcont
stopped in /home/rik/local/share/octave/4.1.0+/m/general/isdir.m at line 26
26:   if (nargin != 1)
debug> dbstack
stopped in:

  -->                         isdir at line 26 [/home/rik/local/share/octave/4.1.0+/m/general/isdir.m]
                            tempdir at line 40 [/home/rik/local/share/octave/4.1.0+/m/miscellaneous/tempdir.m]
                       __makeinfo__ at line 120 [/home/rik/local/share/octave/4.1.0+/m/help/__makeinfo__.m]
      print_usage>get_usage_texinfo at line 129 [/home/rik/local/share/octave/4.1.0+/m/help/print_usage.m]
                        print_usage at line 60 [/home/rik/local/share/octave/4.1.0+/m/help/print_usage.m]
                               poly at line 58 [/home/rik/local/share/octave/4.1.0+/m/polynomial/poly.m]

Closing report.

Lachlan,

I forgot to cc myself (now done) so forgot all about this bug, sorry for that. Happens with more bugs I try, I should be more careful in that respect.
Somewhere in the next days I'll try the new patch.

Oops, this is the file I meant...


(file #36938)

Philip, the file  foo.m  defines a function "foo".  It is not a script.  When you source the file, it places the function "foo" in the symbol table, rather than executing it.  That is why it doesn't print "Hello!", and why it is a command line function after running the file.

The bug in my code is that I call "find" to see if the symbol is already in the symbol table, but I didn't realise that "find" actually loads the symbol. Thus, after the find(), "foo" already points to the function and is not considered a "script".

I'll have to find a way to query the symbol table without loading a symbol.

I've just noticed that I forgot to upload the revised patch.

Philip, can you see if this fixes the problems you saw at bug #47585?

(file #36851)

Rik, it turns out that the reason  run isdir  didn't return anything is that run does nothing if its argument is a function not a script.

I've extended the patch to throw an error if the argument to source (used by run) exists but is not a script.  It still silently returns if the file doesn't exist, so that we don't get an error about ./.octaverc not existing.

The existing code also has a memory leak where the parse tree of the newly parsed file is not deleted if it is not a script.  The patch fixes that too.

(My previous post was also too rushed; I thought that the error messages were for the run case, not for calling isdir directlly.)

Lachlan, after applying your patch to 4.1.0+:

>> dbstop isdir 26
ans =  26
>> isdir
stopped in /home/philip/devel/octdev/oct410+VExTS/../dev_VExTS/scripts/general/isdir.m at line 26
26:   if (nargin != 1)
debug> dbcont
stopped in /home/philip/devel/octdev/oct410+VExTS/../dev_VExTS/scripts/general/isdir.m at line 26
26:   if (nargin != 1)
debug> dbcont
error: Invalid call to isdir.  Correct usage is:

 -- isdir (F)

Additional help for built-in functions and operators is
available in the online version of the manual.  Use the command
'doc <topic>' to search the manual index.

Help and information about Octave is also available on the WWW
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mailing list.
>> run isdir
>> run isdir
>>

I may not understand fully, but isn't the breakpoint supposed to be hit when doing "run isdir", similarly to just "isdir" ?

The problem is still open, so the bug should remain open. I won't be working on this, though.

Btw, asking around, I think Matlab behaves differently here. Doing "run" on a function file executes the function defined there, but apparently it's impossible to pass it parameters with this syntax. Since Octave allows defining functions in a script file unlike Matlab, perhaps this different behaviour should persist? In which case your suggestions would apply.

If you set a breakpoint with

   dbstop foo 2

but use the run command instead of just using the function's name

   run foo.m

Then the breakpoint isn't hit. See this discussion: http://octave.1599824.n4.nabble.com/dbstop-doesn-t-break-with-run-script-td3551242.html