Often when I write a loop I want to run some code at loop entry time. It
would be nice to have a closure trait for this, similar to NEXT for loop
continuation or LAST for loop termination, but there isn't one. I don't
think either FIRST or ENTER do quite what I want. FIRST runs only once,
JG == Joe Gottman [EMAIL PROTECTED] writes:
JGsub use_first()
JG{
JG for 1..2 {
JG FIRST {say 'entering loop';}
JG say $_;
JG LAST{say 'leaving loop';}
JG }
JG }
JG The first time use_first is called it will print
JG
On Sat, Feb 12, 2005 at 12:44:05PM -0500, Uri Guttman wrote:
: JG == Joe Gottman [EMAIL PROTECTED] writes:
:
: JGsub use_first()
: JG{
: JG for 1..2 {
: JG FIRST {say 'entering loop';}
: JG say $_;
: JG LAST{say
LW == Larry Wall [EMAIL PROTECTED] writes:
LW : JG The first time use_first is called it will print
LW : JG entering loop
LW : JG 1
LW : JG 2
LW : JG leaving loop
LW :
LW : JG but subsequently it will print
LW : JG 1
LW : JG 2
LW : JG leaving
On Sat, Feb 12, 2005 at 03:55:40PM -0500, Uri Guttman wrote:
: LW What's going on here is that the loop body is a closure that is
: LW cloned upon entry to the loop (you're logically passing a closure
: LW to the for() function that implements the loop), so if there's a
: LW FIRST inside,
