Re: [Help-smalltalk] I can't find out where the error is

[Stephen Compall]

Canol Gokel <address@hidden> writes:
> Object: nil error: did not understand #value
> MessageNotUnderstood(Exception)>>signal
> UndefinedObject(Object)>>doesNotUnderstand: #value
> True>>and:
> UndefinedObject>>executeStatements
>
> I guess there is an object which is sent a "value" message but the
> object is a "nil" object so it does not understand the message. But I
> have more than one "value" messages so I absolutely don't know where
> the error is.

Well, considering that the backtrace is innermost-first, it's pretty
clear that the specific #value message is one within the method
True>>and:, not one you wrote yourself (unless you changed that method
for some reason).  So you are looking for an #and: that you wrote, not a
#value.  I would guess that you passed a non-block as the argument.

If you want a short-circuiting variant of #and: that doesn't require
making the argument as a block, you'll have to use Presource:

NoCandy.MyCodeMindset installIn: MyNamespace!
MyNamespace.MyCodeMindset messageMacroDictionary
    at: #andf:
    put: (NoCandy.Presrc.PatternMacro
              given: 'address@hidden `andf: address@hidden'
              use: 'address@hidden and: address@hidden')!

> It would be very helpful if all the errors were represented with line
> numbers.

Indeed.

-- 
But you know how reluctant paranormal phenomena are to reveal
themselves when skeptics are present. --Robert Sheaffer, SkI 9/2003