#! /usr/bin/perl -w
#
# This filter works with the internal noweb(1) representation and marks
# definitions of symbols in ocaml(1) source code.  

$code = 0;

while (defined($line = <>)) {
    
    print $line;
    
    $code       = ($line =~ /^\@begin code/) ? 1 : $code;
    $code       = ($line =~ /^\@end code/)   ? 0 : $code;
    
    # make sure we only index code we know how to deal with

    # *.ml
    if ($line =~ /^\@text (let|and|external)\s+(rec\s+)?([-a-zA-Z0-9_']+)/) {
        $id    = $3;
        printf "\@index localdefn %s\n", $id;
        next ;
    }
    if ($line =~ /^\@text (let|and)\s+(rec\s+)?\(\s*([-!$%&*+\/<=>?@^|~:.a-zA-Z0-9_']+)\s*\)/) {
        $id    = $3;
        printf "\@index localdefn %s\n", $id;
        next ;
    }

    # *.mli - symbols are externally visible
    if ($line =~ /^\@text \s{0,10}(val|external)\s+(rec\s+)?([a-zA-Z0-9_'-]+)/) {
        $id    = $3;
        printf "\@index defn %s\n", $id;
        next ;
    }
    if ($line =~ /^\@text \s{0,10}val\s+\(\s*([-!$%&*+\/<=>?@^|~:.a-zA-Z0-9_']+)\s*\)/) {
        $id    = $1;
        printf "\@index localdefn %s\n", $id;
        next ;
    }

    # *.mly - non terminals
    if ($line =~ /^\@text ([a-zA-Z0-9]+)\s*:/) {
        $id    = $1;
        printf "\@index localdefn %s\n", $id;
        next ;
    }
    
    # *.mll - scanner contexts
    if ($line =~ /^\@text (rule|and)\s+([a-zA-Z0-9]+)\s*=/) {
        $id    = $2;
        printf "\@index localdefn %s\n", $id;
        next ;
    }
}