Do you use mozilla?
http://mozilla.org/
Do you use keywords?
http://www.mozilla.org/docs/end-user/internet-keywords.html
Do you use custom keyword queries?
http://www.mozilla.org/docs/end-user/keywords.html
Do you want your custom keyword queries to
- relace *all* instances of the token in your URI template?
- allow multiple arguments to be place in multiple places?
- allow some args to be url-encoded, but not others?
Then you want to take this perl code as a starting point for your own
CGI script or Apache module. Then set up a custom keyword to call that
script or module and you're home free (modulus one HTTP transaction per
call).
See also
http://use.perl.org/user/miyagawa/journal/6929
http://use.perl.org/user/miyagawa/journal/6930
This code predates the above, but miyagawa's posting reminded me
that other folks might find use for it...
http://bugzilla.mozilla.org/show_bug.cgi?id=124237
http://bugzilla.mozilla.org/attachment.cgi?id=69884&action=view
I'm m_mozilla, so feel free to copy/adapt/whatever this code to
your heart's desire.
WARNING:
Slash wraped the long URLs.
The tests won't work until you unwrap them.
-matt
#!/usr/bin/perl -w
$::verbose = 0; # turn on to enable verbose testing (to STDOUT)
use strict;
print "testing...\n";
&test_uri_template_code;
print "testing complete.\n";
sub build_uri ($$) { # Q=plain, q=encode
my( $uri_t, $query ) = @_;
return undef unless defined $uri_t;
return $uri_t unless $uri_t =~ m/%[qQ]\d*;/;
return &empty_tokens( $uri_t )
unless ( defined $query and $query =~ /\S/ );
$uri_t =~ s/%([qQ])0*(\d+);/%$1$2;/g;
$query =~ s/^\s+|\s+$//g;
my @terms = split( /\s+/, $query);
my @numeric_tokens = sort { $a <=> $b } ( keys %{{
map { $_ => 1 } ( $uri_t =~ m/%[qQ](\d+);/g )
}}); # <=> sorted uniq numbers from %[qQ](\d+); tokens
while ( @terms and @numeric_tokens ) {
my $term = shift @terms;
my $token = shift @numeric_tokens;
$uri_t =~ s{%([qQ])$token;}{ $1 eq 'Q'
? $term : &uri_encode( $term )
}ge;
} # now we're out of @terms and/or @numeric_tokens
return &empty_tokens( $uri_t ) unless @terms;
return $uri_t unless $uri_t =~ m/%[qQ]\d*;/;
$uri_t =~ s{%([qQ]);}{ $1 eq 'Q'
? join( '+', @terms )
: uri_encode( join( ' ', @terms ) )
}ge;
return $uri_t;
}
sub empty_tokens ($) {
local $_ = shift; s/%[qQ]\d*;//g; return $_;
}
sub uri_encode {
return undef unless $_[0];
my $txt = shift;
# use a real look-up table in mozilla; faster than this:
$txt =~ s/([^a-zA-Z0-9~._\-])/$1 eq' '?'+':sprintf("%%%02X",ord($1))/ge;
return $txt;
}
sub test_uri_template_code {
# keywords containing '_x_' have malformed URI templates, and
# the test results will need to not treat bad tokens as tokens
%::keywords2templates = qw{
a http://www.alldirect.com/
a_x_1 http://www.alldirect.com/%q
a_x_2 http://www.alldirect.com/%q1
a_x_3 http://www.alldirect.com/%qx
a_x_4 http://www.alldirect.com/%qx;
a_x_5 http://www.alldirect.com/%q0
a_x_6 http://www.alldirect.com/%q01
a_x_7 http://www.alldirect.com/%1;
a_x_8 http://www.alldirect.com/%20;
a_x_9 http://www.alldirect.com/%1$q
a_x_10 http://www.alldirect.com/^%1$q
a_x_11 http://www.alldirect.com/%qabout.asp
isbninfo http://www.amazon.com/exec/obidos/ASIN/%q1;
isbnbuy http://www.alldirect.com/book.asp?isbn=%q1;
isbnbuy_1 http://www.alldirect.com/book.asp?isbn=%q;
isbnbuy_2 http://www.alldirect.com/book.asp?isbn=%q01;
isbnbuy_3 http://www.alldirect.com/book.asp?isbn=%q001;
isbnbuy_4 http://www.alldirect.com/book.asp?isbn=%q000000001;
isbnbuy_5 http://www.alldirect.com/book.asp?isbn=%q0;
isbnbuy_6 http://www.alldirect.com/book.asp?isbn=%q00000000;
isbnbuy_7 http://www.alldirect.com/book.asp?isbn=%q00000700;
chart http://quote.fool.com/Chart/chart.asp?time=%q1;&symbols=%q2;
chart_1 http://quote.fool.com/Chart/chart.asp?time=%q7;&symbols=%q025;
chart_2 http://quote.fool.com/Chart/chart.asp?time=%q7;&symbols=%q;
chart_x_1 http://quote.fool.com/Chart/chart.asp?time=%qq;&symbols=%q;
chart_x_2 http://quote.fool.com/Chart/chart.asp?time=%;&symbols=%0q;
chart_reverse http://quote.fool.com/Chart/chart.asp?time=%q2;&symbols=%q1;
chart_reverse_1 http://quote.fool.com/Chart/chart.asp?time=%q001;&symbols=%q000;
chart_reverse_2 http://quote.fool.com/Chart/chart.asp?time=%q;&symbols=%q0;
bughunt http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=%q;&field0-0-1=component&type0-0-1=substring&value0-0-1=%q;&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=%q;&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=%q;
bughunt_first_term_only http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=%q0;&field0-0-1=component&type0-0-1=substring&value0-0-1=%q0;&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=%q0;&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=%q0;
bughunt_ordered_terms http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=%q0;&field0-0-1=component&type0-0-1=substring&value0-0-1=%q1;&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=%q2;&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=%q3;
owner_a_bughunt_queryb http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=%q;&field0-0-1=component&type0-0-1=substring&value0-0-1=%q;&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=%q;&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=%q;&email1=%q0;&emailtype1=exact&emailassigned_to1=1
reporter_a_bughunt_queryb http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=%q;&field0-0-1=component&type0-0-1=substring&value0-0-1=%q;&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=%q;&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=%q;&email1=%q0;&emailtype1=exact&emailreporter1=1
anyemail_a_bughunt_queryb http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=%q;&field0-0-1=component&type0-0-1=substring&value0-0-1=%q;&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=%q;&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=%q;&email1=%q0;&emailtype1=exact&emailassigned_to1=1&emailreporter1=1&emailqa_contact1=1&emailcc1=1&emaillongdesc1=1
val_mozilla_page http://validator.w3.org/check?uri=http%3A%2F%2Fmozilla.org%2F%q;
val_mozilla_page_to_html_v http://validator.w3.org/check?uri=http%3A%2F%2Fmozilla.org%2F%q1;&doctype=%q;
drivefromhome_to_a http://maps.yahoo.com/py/ddResults.py?newaddr=123+Home+Ave&newcsz=12345&taraddr=%Q1;&tarcsz=%q2;
drivefrom_a_to_b http://maps.yahoo.com/py/ddResults.py?newaddr=%Q1;&newcsz=%q2;&taraddr=%Q3;&tarcsz=%q4;
trans_parturl_a_from_b_2c http://fets3.freetranslation.com:5081/?Language=%q2;%2F%q3;&Url=%q1;&Sequence=core
trans_parturl_a_from_b_2c_1 http://fets3.freetranslation.com:5081/?Language=%q22;%2F%q33;&Url=%q11;&Sequence=core
trans_parturl_a_from_b_2c_2 http://fets3.freetranslation.com:5081/?Language=%q00022;%2F%q033;&Url=%q000011;&Sequence=core
trans_parturl_a_from_b_2c_3 http://fets3.freetranslation.com:5081/?Language=%q00022;%2F%q;&Url=%q0;&Sequence=core
trans_from_a_2b_parturl_c http://fets3.freetranslation.com:5081/?Language=%q1;%2F%q2;&Url=%q3;&Sequence=core
};
my %canonical_testcases = (
# for each testcase, [q{query string}, q{expected resuting URI}]
'a' => [
[ q{doesn't matter what args you put here, they should all be ignored},
q{http://www.alldirect.com/},
],
],
'isbninfo' => [
[ q{0596000529},
q{http://www.amazon.com/exec/obidos/ASIN/0596000529},
],[ q{0596000529 additional args ignored. Book title is Creating Applications with Mozilla},
q{http://www.amazon.com/exec/obidos/ASIN/0596000529},
],[ q{ 0596000529 initial whitespace also ignored},
q{http://www.amazon.com/exec/obidos/ASIN/0596000529},
],
],
'isbnbuy' => [
[ q{0764545884},
q{http://www.alldirect.com/book.asp?isbn=0764545884},
],[ q{0764545884 additional args ignored. Book title is Mozilla Source Code Guide with CDROM},
q{http://www.alldirect.com/book.asp?isbn=0764545884},
],
],
'chart' => [
[ q{1mo aapl},
q{http://quote.fool.com/Chart/chart.asp?time=1mo&symbols=aapl},
],[ q{3mo aapl},
q{http://quote.fool.com/Chart/chart.asp?time=3mo&symbols=aapl},
],[ q{ytd aapl},
q{http://quote.fool.com/Chart/chart.asp?time=ytd&symbols=aapl},
],[ q{2yr aapl},
q{http://quote.fool.com/Chart/chart.asp?time=2yr&symbols=aapl},
],[ q{all aapl},
q{http://quote.fool.com/Chart/chart.asp?time=all&symbols=aapl},
],[ q{ytd msft},
q{http://quote.fool.com/Chart/chart.asp?time=ytd&symbols=msft},
],[ q{ 1mo aapl whitespace and extra args ignored},
q{http://quote.fool.com/Chart/chart.asp?time=1mo&symbols=aapl},
],
],
'chart_reverse' => [
[ q{ aapl 1mo like above, but for those who prefer reversed syntax},
q{http://quote.fool.com/Chart/chart.asp?time=1mo&symbols=aapl},
],
],
'bughunt' => [ # bonus: bug 98749 gets fixed too!
[ q{custom keywords},
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=custom+keywords&field0-0-1=component&type0-0-1=substring&value0-0-1=custom+keywords&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=custom+keywords&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=custom+keywords},
],[ q{not suck},
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=not+suck&field0-0-1=component&type0-0-1=substring&value0-0-1=not+suck&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=not+suck&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=not+suck},
],
],
'bughunt_first_term_only' => [
[ q{tabs and additional args are ignored},
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=tabs&field0-0-1=component&type0-0-1=substring&value0-0-1=tabs&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=tabs&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=tabs},
]
],
'owner_a_bughunt_queryb' => [
[ q{ben@netscape.com custom keywords},
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=custom+keywords&field0-0-1=component&type0-0-1=substring&value0-0-1=custom+keywords&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=custom+keywords&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=custom+keywords&email1=ben%40netscape.com&emailtype1=exact&emailassigned_to1=1},
],[ q{peterv@netscape.com white-space: pre},
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=white-space%3A+pre&field0-0-1=component&type0-0-1=substring&value0-0-1=white-space%3A+pre&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=white-space%3A+pre&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=white-space%3A+pre&email1=peterv%40netscape.com&emailtype1=exact&emailassigned_to1=1},
],
],
'reporter_a_bughunt_queryb' => [
[ q{asa@mozilla.org crash causes},
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=crash+causes&field0-0-1=component&type0-0-1=substring&value0-0-1=crash+causes&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=crash+causes&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=crash+causes&email1=asa%40mozilla.org&emailtype1=exact&emailreporter1=1},
],
],
'anyemail_a_bughunt_queryb' => [
[ q{hewitt@netscape.com tooltip},
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=tooltip&field0-0-1=component&type0-0-1=substring&value0-0-1=tooltip&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=tooltip&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=tooltip&email1=hewitt%40netscape.com&emailtype1=exact&emailassigned_to1=1&emailreporter1=1&emailqa_contact1=1&emailcc1=1&emaillongdesc1=1},
],[ q{bryner@netscape.com}, # leaves normal query part empty, makes bugzilla work for very long time :/
q{http://bugzilla.mozilla.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&field0-0-0=product&type0-0-0=substring&value0-0-0=&field0-0-1=component&type0-0-1=substring&value0-0-1=&field0-0-2=short_desc&type0-0-2=substring&value0-0-2=&field0-0-3=status_whiteboard&type0-0-3=substring&value0-0-3=&email1=bryner%40netscape.com&emailtype1=exact&emailassigned_to1=1&emailreporter1=1&emailqa_contact1=1&emailcc1=1&emaillongdesc1=1},
],
],
'val_mozilla_page' => [
[ q{mozorg.html},
q{http://validator.w3.org/check?uri=http%3A%2F%2Fmozilla.org%2Fmozorg.html},
],[ q{ports/fizzilla/Cocoazilla.html},
q{http://validator.w3.org/check?uri=http%3A%2F%2Fmozilla.org%2Fports%2Ffizzilla%2FCocoazilla.html},
],
],
'val_mozilla_page_to_html_v' => [
[ q{ports/fizzilla/Cocoazilla.html HTML 4.01 Strict},
q{http://validator.w3.org/check?uri=http%3A%2F%2Fmozilla.org%2Fports%2Ffizzilla%2FCocoazilla.html&doctype=HTML+4.01+Strict},
],[ q{ports/fizzilla/Cocoazilla.html XHTML 1.0 Transitional},
q{http://validator.w3.org/check?uri=http%3A%2F%2Fmozilla.org%2Fports%2Ffizzilla%2FCocoazilla.html&doctype=XHTML+1.0+Transitional},
],
],
'drivefromhome_to_a' => [
[ q{999+EndHere+Ave 56789},
q{http://maps.yahoo.com/py/ddResults.py?newaddr=123+Home+Ave&newcsz=12345&taraddr=999+EndHere+Ave&tarcsz=56789},
],[ q{666+Brimstone+Ave 00666},
q{http://maps.yahoo.com/py/ddResults.py?newaddr=123+Home+Ave&newcsz=12345&taraddr=666+Brimstone+Ave&tarcsz=00666},
],
],
'drivefrom_a_to_b' => [
[ q{111+StartHere+Blvd 12345 999+EndHere+Ave 56789},
q{http://maps.yahoo.com/py/ddResults.py?newaddr=111+StartHere+Blvd&newcsz=12345&taraddr=999+EndHere+Ave&tarcsz=56789},
],[ q{111+StartHere+Blvd 12345 999+EndHere+Ave 56789 all other args ignored},
q{http://maps.yahoo.com/py/ddResults.py?newaddr=111+StartHere+Blvd&newcsz=12345&taraddr=999+EndHere+Ave&tarcsz=56789},
],
],
'trans_parturl_a_from_b_2c' => [
[ q{mozilla.org English Spanish},
q{http://fets3.freetranslation.com:5081/?Language=English%2FSpanish&Url=mozilla.org&Sequence=core},
],[ q{mozilla.org English French},
q{http://fets3.freetranslation.com:5081/?Language=English%2FFrench&Url=mozilla.org&Sequence=core},
],[ q{mozilla.org English German},
q{http://fets3.freetranslation.com:5081/?Language=English%2FGerman&Url=mozilla.org&Sequence=core},
],[ q{mozilla.org English Italian},
q{http://fets3.freetranslation.com:5081/?Language=English%2FItalian&Url=mozilla.org&Sequence=core},
],[ q{mozilla.org English Norwegian},
q{http://fets3.freetranslation.com:5081/?Language=English%2FNorwegian&Url=mozilla.org&Sequence=core},
],[ q{mozilla.org English Portuguese},
q{http://fets3.freetranslation.com:5081/?Language=English%2FPortuguese&Url=mozilla.org&Sequence=core},
],[ q{mx.yahoo.com Spanish English},
q{http://fets3.freetranslation.com:5081/?Language=Spanish%2FEnglish&Url=mx.yahoo.com&Sequence=core},
],[ q{de.yahoo.com German English},
q{http://fets3.freetranslation.com:5081/?Language=German%2FEnglish&Url=de.yahoo.com&Sequence=core},
],
],
'trans_from_a_2b_parturl_c' => [
[ q{German English de.yahoo.com},
q{http://fets3.freetranslation.com:5081/?Language=German%2FEnglish&Url=de.yahoo.com&Sequence=core},
],[ q{Spanish English mx.yahoo.com},
q{http://fets3.freetranslation.com:5081/?Language=Spanish%2FEnglish&Url=mx.yahoo.com&Sequence=core},
],[ q{English Italian mozilla.org},
q{http://fets3.freetranslation.com:5081/?Language=English%2FItalian&Url=mozilla.org&Sequence=core},
],[ q{English French mozilla.org},
q{http://fets3.freetranslation.com:5081/?Language=English%2FFrench&Url=mozilla.org&Sequence=core},
],
],
);
for my $keyword ( keys %canonical_testcases ) {
for my $pair ( @{$canonical_testcases{$keyword}} ) {
&report_on_keyword_with_input( $keyword, @$pair );
}
}
my %additional_testcases = (
# like above, but for catching bizarre bugs. As bugs come up,
# fix them and add a relevant test case or two in here.
);
for my $keyword ( keys %additional_testcases ) {
for my $pair ( @{$additional_testcases{$keyword}} ) {
&report_on_keyword_with_input( $keyword, @$pair );
}
}
}
sub report_on_keyword_with_input {
my( $keyword, $query, $expected ) = @_;
my $uri_t = $::keywords2templates{ $keyword };
my $result = &build_uri( $uri_t, $query );
if ( defined $result ) {
my $ok = $result eq $expected;
if ( $ok and $::verbose ) {
print "... Correct URI when expanding: $keyword $query\n";
} elsif ( !$ok ) {
print "!!! Unexpected URI when expanding: $keyword $query\n";
print " looking for: $expected\n";
print " but I found: $result\n";
}
} else {
print "!!! Undefined URI when expanding: $keyword $query\n";
}
}
What's the point of using function prototypes if you use the sigil for calling them? (Yeah, I do think the ampersand is a very nearly an abomination.)
Re:Pedant
wickline on 2002-08-07T10:53:59
To be honest, I use both for documentation more than anything else.
I've benefited from this use, and have yet to be bit by it, so I just
keep on doing it...
I've used ampersands as a sigil since I started writing perl because
it makes it plain that we're talking about a subroutine. It also reads
well:
&load_data; &collate_records;
"...and load data and collate records"
It also allows me to have more control when doing a s///g on my own
code. &foo is never confused with @foo{'foo',$foo,$foo{$foo},@foo}.
If I want to rename a subroutine to something more appropriate, or
even just find every place where it's used, I can do so without a
bunch of false positives. I also like to use parens around my args
when I don't strictly need them... it's free documentation, and also
lets me easily select the whole list of args to copy/paste/replace
them (BBEdit lets you double click on a paren/bracket/brace to select
the whole block, or command-B from within the block).
I tend not to use ampersands for functions imported from modules,
because I'd rather allow any type checking to proceed and I'm not very
likely to be re-naming them. This also makes them look more like built
in functions, which is how I'd rather think of those imported subs.
I don't always use prototypes. When I do use them, I do it more as a
way of telling someone reading the code "hey, this sub takes these args" rather than to tell perl anything about the sub. The prototype
plus the initial assignment from @_ can tell someone immediately that
you're not using @_ any further, or that you're going to be doing
something with "everything left in @_" later on in the subroutine.
Yes, I know I'm missing out on some handy error-checking by using the
ampersand as a sigil, but I personally find the sigil more useful than
the error-checking. I'm much much more likely to be greatful for an
unambiguous string to identify calls to my subroutines than I am to be
greatful for some arg-checking by perl.
In production code, I do document my subs, but sometimes when you're
debugging it's easy to just look at the code and ignore the POD. The
prototype is just a bonus bit of documentation.
Bad habit? Maybe. I work with some folks who are learning perl and so
far it seems to work well for them. They don't tend to have problems
figuring out what sorts of args to use for a function. They do like
that they can see at a glance what is a subroutine call and what is
a call to a built-in function (or imported sub).
-matt
