Re: Matlab test

[Ben Abbott]

On May 17, 2013, at 9:09 AM, Michael Goffioul wrote:

> On Thu, May 16, 2013 at 8:34 PM, Ben Abbott <address@hidden> wrote:
> On May 17, 2013, at 7:02 AM, Michael Goffioul wrote:
> 
> > Hi,
> >
> > Can I ask anybody to make a test for me under Matlab. I'm trying to 
> > determine when Matlab actually parses files that are contained in a 
> > package. The only thing I can think of is to put a parse error into one of 
> > the files.
> >
> > So the test would be to have a package, not initially in your path, and a 
> > file (e.g. a function file) in that package, which contains a parse error. 
> > Then use "addpath" to make the package visible, that is adding the parent 
> > of the package directory to the path.
> >
> > So let's say you have the following: a/+pack/invalid_fun.m (invalid_fun.m 
> > has a parse error). Then try the following commands (if any of the command 
> > produces an error, don't bother going further):
> >
> > addpath a
> > p = meta.package.fromName('pack')
> > fcn = p.Functions{1}
> > fcn()
> >
> > Michael.
> 
> I used a trivial function
> 
> function a = invalid_fun (a)
>   a = a .+ 1;
> end
> 
> Then ...
> 
> addpath ('~/Documents/MATLAB/a')
> matlab>p = meta.package.fromName('pack')
> 
> p =
> 
>   package with properties:
> 
>                  Name: 'pack'
>             ClassList: [0x1 meta.class]
>          FunctionList: [1x1 meta.method]
>           PackageList: [0x1 meta.package]
>     ContainingPackage: []
> 
> matlab>fcn = p.Functions{1}
> 
> fcn =
> 
>   method with properties:
> 
>                    Name: 'invalid_fun'
>             Description: ''
>     DetailedDescription: ''
>                  Access: 'public'
>                  Static: 0
>                Abstract: 0
>                  Sealed: 0
>                  Hidden: 0
>              InputNames: {'rhs1'}
>             OutputNames: {'lhs1'}
>           DefiningClass: []
> 
> matlab>fcn()
> 
> ans =
> 
>   method with properties:
> 
>                    Name: 'invalid_fun'
>             Description: ''
>     DetailedDescription: ''
>                  Access: 'public'
>                  Static: 0
>                Abstract: 0
>                  Sealed: 0
>                  Hidden: 0
>              InputNames: {'rhs1'}
>             OutputNames: {'lhs1'}
>           DefiningClass: []
> 
> And I get no error.  Have I done something wrong?  I'm not familiar with the 
> meta.packages.  How may I actually call the function?
> 
> You actually call it with "pack.invalid_fun()".

Ok.  That triggers the parser.

pack.invalid_fun(1)
Error using pack.invalid_fun
Error: File: invalid_fun.m Line: 2 Column: 10
Unexpected MATLAB operator.

> But the documentation says that the "Functions" property return a cell array 
> of function handles. Apparently, there's some confusion about what "function 
> handle" means. In this case, it looks like it is a meta.method object instead 
> (and meta.method class inherits from handle class).
> 
> This makes me wonder what would be the result if
> 1) the parse error was in the function definition line instead

I changed the function to ...

function a = invalid_fun (a++)
  a = a;
end

matlab> clear all
matlab> p = meta.package.fromName('pack')

p = 

  package with properties:

                 Name: 'pack'
            ClassList: [0x1 meta.class]
         FunctionList: [1x1 meta.method]
          PackageList: [0x1 meta.package]
    ContainingPackage: []

matlab> fcn = p.Functions{1}

fcn = 

  method with properties:

                   Name: 'invalid_fun'
            Description: ''
    DetailedDescription: ''
                 Access: 'public'
                 Static: 0
               Abstract: 0
                 Sealed: 0
                 Hidden: 0
             InputNames: {'rhs1'}
            OutputNames: {'lhs1'}
          DefiningClass: []

>> pack.invalid_fun (1)
Error using pack.invalid_fun
Error: File: invalid_fun.m Line: 1 Column: 28
Unexpected MATLAB operator.

> 2) invalid_fun.m was an invalid classdef definition file instead: I would 
> expect it to appear in p.Classes instead, though if the parse error is in the 
> classdef line (for instance "classde invalid_class < handle"), what would it 
> do?

You'd like the content of invalid_fun.m to be ...

classde invalid_class < handle
end

Using this I get ...

matlab> clear all
matlab> p = meta.package.fromName('pack')

p = 

  package with properties:

                 Name: 'pack'
            ClassList: [0x1 meta.class]
         FunctionList: [1x1 meta.method]
          PackageList: [0x1 meta.package]
    ContainingPackage: []

matlab> fcn = p.Functions{1}

fcn = 

  method with properties:

                   Name: 'invalid_fun'
            Description: ''
    DetailedDescription: ''
                 Access: 'public'
                 Static: 0
               Abstract: 0
                 Sealed: 0
                 Hidden: 0
             InputNames: {'rhs1'}
            OutputNames: {'lhs1'}
          DefiningClass: []

matlab> pack.invalid_fun (1)
Error using pack.invalid_fun
Error: File: invalid_fun.m Line: 2 Column: 1
Illegal use of reserved keyword "end".

Ben