Re: Why doesn't foreach return a value

You are attempting to return a non-initialized variable as
the body of the foreach command never is executed.

I'm not a tcl expert, but what would this return, may I ask:

proc test {l} {
set itemcount 0
foreach a $l {incr itemcount}
return $itemcount
}

An empty list should return zero itemcount, it would return
one in your scheme, wouldn't it?

As would a single-element list.

(never mind that you should use llength $l )

Rufus


"Mark Janssen" <mpc.janssen@xxxxxxxxx> wrote in message
news:8cb11668-0180-4297-a8b8-8a99889a3815@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Is there any specific reason a call to foreach always returns {}? It
would be useful if it returns the last result. I could have used this
on occasion. For instance a bit of a crafted example:

proc test {l} {
foreach a $l {append b $a}
return $b
}

fails in the case $l eq {}. It needs to be:

proc test {l} {
set b {}
foreach a $l {append b $a}
return $b
}

with foreach returning a value (or {} if the body doesn't execute)
this would be:

proc test {l} {
foreach a $l {append _ $l}
}

Mark


.

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