Using tcl, i want to pass variable parameters to function. i tried this code
proc launch_proc { msg proc_name {params {}} } {
puts "params launch_proc is $params \n"
}
proc test { param } {
puts "param test is $param \n"
launch_proc "1.5.2 test param" test_standard {{*}$param param1 param2 param3"
}
}
test value
--> params launch_proc is {*}$param param1 param2 param3" $param is not evaluated (i use tcl 8.5)
Tcl has support for this using the keyword args as the last parameter in the argument list.
Here is an example directly from the wiki:
proc demo {first {second "none"} args} {
puts "first = $first"
puts "second = $second"
puts "args = $args"
}
demo one
demo one two
demo one two three four five
results in
first = one
second = none
args =
first = one
second = two
args =
first = one
second = two
args = three four five
You can use the expand syntax for this as well which makes the following two calls to demo equivalent.
demo one two three four five
set params {three four five}
demo one two {*}$params
You're passing a list and need to instead send each item as a parameter to the proc.
proc test {p1 p2 p3} {
puts "$p1 - $p2 - $p3"
}
set value {one two three}
# This should work in tcl 8.5+
test {*}$value
set value {four five six}
# For tcl < 8.5
foreach {p1 p2 p3} $value {
test $p1 $p2 $p3
break
}
# or
set value {seven eight nine}
test [lindex $value 0] [lindex $value 1] [lindex $value 2]
Output:
$ tclsh test.tcl
one - two - three
four - five - six
seven - eight - nine
You need upvar, and use list when you construct the params list for launch_proc
proc test {varname} {
upvar 1 $varname value
puts "param test is $varname => $value"
launch_proc "1.5.2 test param" test_standard [list {*}$value par1 par2 par3]
}
proc launch_proc {msg proc_name {params {}}} {
puts "params launch_proc: [join $params ,]"
}
set value {"a b c" "d e f" "g h i"}
test value
param test is value => "a b c" "d e f" "g h i"
params launch_proc: a b c,d e f,g h i,par1,par2,par3
launch_proc, but you are passing more than (incorrect ?) that. Also, issues with the quoting as well.{*}$param param1 param2 param3tolaunch_proc. It does not look like what you want. Did you meanlaunch_proc "1.5.2 test param" test_standard "{*}$param param1 param2 param3"?launch_proc "1.5.2 test param" test_standard [list {*}$param param1 param2 param3]$valuecontain any value when you invoke thetestproc?