bugGNU Octave - Bugs: bug #38758, Parser oddity with 'if' statements...


bug #38758: Parser oddity with 'if' statements and spurious display with nargin

Submitted by:  Guillaume <gyom>
Submitted on:  Wed 17 Apr 2013 11:25:53 AM UTC  
Category: InterpreterSeverity: 3 - Normal
Priority: 5 - NormalItem Group: Other
Status: FixedAssigned to: John W. Eaton <jwe>
Originator Name: GuillaumeOpen/Closed: Closed
Release: devOperating System: Any

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Thu 20 Jun 2013 02:13:10 AM UTC, comment #3:

I checked in the following change.


John W. Eaton <jwe>
Project AdministratorIn charge of this item.
Wed 19 Jun 2013 10:46:18 PM UTC, comment #2:

I think the problem is also related to the path the parser is taking through if statements. For example, using a pair of parentheses around the condition of the if statement also fixes the problem.

Ordinarily code of the form


is equivalent to


as the comma just tells the parser that a new statement has begun. This seems to be the case here for whatever reason.

In fact, I would guess that the problem is that the if conditional is not being greedy enough and stops after accepting nargin. Thus, the parsing results in

Rik <rik5>
Project Administrator
Sat 11 May 2013 10:06:44 AM UTC, comment #1:


Clemens Buchacher <drizzd>
Wed 17 Apr 2013 11:25:53 AM UTC, original submission:

Since recent changes in the Octave parser, I observe spurious displays due to lines such as:

it displays:

It doesn't happen with different call syntax:

Guillaume <gyom>


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  • -unavailable- added by jwe (Updated the item)
  • -unavailable- added by rik5 (Posted a comment)
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  • -unavailable- added by jordigh (Updated the item)
  • -unavailable- added by drizzd (Posted a comment)
  • -unavailable- added by gyom (Submitted the item)

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    Follow 6 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Thu 20 Jun 2013 02:13:10 AM UTCjweStatusConfirmed=>Fixed
    Wed 19 Jun 2013 11:57:52 PM UTCjweAssigned toNone=>jwe
    Wed 19 Jun 2013 10:46:18 PM UTCrik5SummarySpurious display with nargin=>Parser oddity with 'if' statements and spurious display with nargin
      Carbon-Copy-=>Added jwe
    Sat 11 May 2013 10:44:49 AM UTCjordighStatusNone=>Confirmed

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