Forum OpenACS Q&A: Problems defining procs

my_proc {} "my code goes here"

or this:

my_proc {} [list my code goes here]

In other words, I need to dynamically define this proc. But this doesn't work. It works just fine if I open a tcl interpreter and type the code in there. But it doesn't work in OpenACS for some reason.

If it makes any difference, I am trying to define this proc in a "blah-procs" file to get automatically sourced when the system starts.

Any ideas? Thanks.

What I need is a proc that returns a list of values. The list of values changes day to day. I want the list of values to come from a backend database. I want the proc to be defined dynamically at startup to return that list of values. I don't want to have to connect to the backend database each time I need the list of values - I just want to connect one time at system startup, get the list of values, and have that list of values "hard-coded" in the proc.

This is easy to do. In fact, I've tested it outside of OpenACS and it works just fine (TCL is made to do stuff like this). It just doesn't work in OpenACS for some reason.

Is there some reason why this sort of definition is not possible in OpenACS or AOLServer?

# get/set the values
set day_values "aaa bbb ccc"
set myproc "
proc myproc {} {
puts \"The day's values are: $day_values\"
}
"
eval $myproc

The values get hardcoded into the proc.

If you guys say it works for you, I'll suspect something with my installation.

Nothing in the error logs except the same error I get when I try to access the page that tests the proc - "name of proc" isn't a procedure. Seems as if the proc is not being defined. If I define it the "normal" way (where I can't hardcode info in the proc) it gets defined. If I do it the other way, it apparently doesn't.

To repeat, when I say it is "not working," when I call the web page which uses the proc, I get a "'name of proc' isn't a procedure" error (it doesn't literally say 'name of proc', it uses the actual name of the proc I am trying to define).

Also, to repeat, this is not with a package I am defining, nor an existing package. I am simply using the www directory for my web pages, and I am putting my custom procs in a "blah-procs" file in the tcl folder.

Repeating again, I got the util_memoize to work, but only if I put the proc in a certain location in the "blah-procs" file. If I put it in a different location, I get the same error.

If you guys don't experience any of these problems, and don't believe a bug exists, I'll chalk it up to the installation.

Thanks.

See the documentation on Packages for more information.

[11/Jun/2011:16:47:14][1032.1992][-thread1992-] Error: tcl: source c:/aolserver/servers/openacs/tcl/exchange-procs.tcl failed: no connection
NONE
no connection
while executing
"ns_conn headers"
(procedure "ad_host" line 2)
invoked from within
"ad_host"
(procedure "exch" line 2)
invoked from within
"exch MKT"
(procedure "mkt" line 1)
invoked from within
"mkt"
("eval" body line 1)
invoked from within
"eval $script"
invoked from within
"ns_cache eval util_memoize $script {
list $current_time [eval $script]
}"
(procedure "util_memoize" line 20)
invoked from within
"util_memoize mkt"
(file "c:/aolserver/servers/openacs/tcl/exchange-procs.tcl" line 36)
invoked from within
"source $file"

Don't know what "no connection means." If the other poster above is correct, I should put my code in a package... correct? I didn't want to have to create one, but I will try and report back.

Thanks to all for continuing to help - this is a great community.

Once an error is raised in a tcl file, nothing further in that file will get executed, including commands to define procs. That would explain why the proc is available if you define it early in the file but not at the end.

To get the name of the server you are on when there is no request, use [ns_info hostname], or could you just use "localhost"?

Which is not a way to "dynamically define this proc".