> While I understand that in some cases parens may be necessary to avoid
ambiguities, in the following example I fail to see why they are needed :
>
> this simply prints the list of files in the current folder and works quite
fine :
>
> >> foreach elt read %. [if (get in info? to-file elt 'type) = 'file [print
elt]]

> but when removing the parens we get :
>
> >> foreach elt read %. [if get in info? to-file elt 'type = 'file [print
elt]]
> ** Script Error: in expected word argument of type: word
> ** Where: halt-view
> ** Near: if get in info? to-file

That's because the '= is infix; it grabs the left and right arguments, as it
were. Try this instead:

foreach elt read %. [if 'file = get in info? to-file elt 'type [print elt]]

Andrew Martin
ICQ: 26227169 http://valley.150m.com/
-><-

----- Original Message -----
From: "Laurent Giroud" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, October 06, 2002 10:30 AM
Subject: [REBOL] if and parens


> Hi everyone again,
>
> I have a little "problem" that I encounter quite frequently with 'if : in
> certain cases I need to use parens to make sure that the expression tested
is
> correctly evaluated.
> While I understand that in some cases parens may be necessary to avoid
> ambiguities, in the following example I fail to see why they are needed :
>
> this simply prints the list of files in the current folder and works quite
fine :
>
> >> foreach elt read %. [if (get in info? to-file elt 'type) = 'file [print
elt]]
> ...
>
> but when removing the parens we get :
>
> >> foreach elt read %. [if get in info? to-file elt 'type = 'file [print
elt]]
> ** Script Error: in expected word argument of type: word
> ** Where: halt-view
> ** Near: if get in info? to-file
>
> The code looks quite unambiguous to me since all the part beetween the 'if
and
> the "=" character evaluates without problem if isolated :
>
> >> elt: %afile       ; "afile" being an existing file
> >> get in info? to-file elt 'type
> == file
>
> Would anyone have an explanation ?
>
> Regards,
> Laurent
>
> --
> Laurent Giroud
> mailto:[EMAIL PROTECTED]
>
> --
> To unsubscribe from this list, please send an email to
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