2/lcats: Line Categories.

@Purpose: We are going to need to identify lines of source code as
falling into 18 different categories -- the start of a definition, a
piece of a comment, and so on. In this section we define constants to
enumerate these categories, and provide a debugging routine to show the
classification we are using on the web we've just read.

@Definitions:

@ The line categories are enumerated as follows:

@d $NO_LCAT 0 # none set as yet
@d $COMMENT_BODY_LCAT 1
@d $MACRO_DEFINITION_LCAT 2
@d $BAR_LCAT 3
@d $INDEX_ENTRY_LCAT 4
@d $PURPOSE_LCAT 5
@d $INTERFACE_LCAT 6
@d $GRAMMAR_LCAT 7
@d $DEFINITIONS_LCAT 8
@d $PARAGRAPH_START_LCAT 9
@d $BEGIN_VERBATIM_LCAT 10
@d $TEXT_EXTRACT_LCAT 11
@d $BEGIN_DEFINITION_LCAT 12
@d $GRAMMAR_BODY_LCAT 13
@d $INTERFACE_BODY_LCAT 14
@d $CODE_BODY_LCAT 15
@d $CONT_DEFINITION_LCAT 19
@d $SOURCE_DISPLAY_LCAT 16
@d $TOGGLE_WEAVING_LCAT 17
@d $COMMAND_LCAT 18

@-------------------------------------------------------------------------------

@ The scanner is intended for debugging |inweb|, and simply shows the main
result of reading in and parsing the web:

@c
sub scan_line_categories {
	my $sigil = $_[0];
	my $confine_to = -1;
	my $sn;
	my $i;
	for ($sn=0; $sn<$no_sections; $sn++) {
		if ($section_sigil[$sn] eq $sigil) {
			$confine_to = $sn;
		}
	}
	for ($i=0; $i<$no_lines; $i++) {
		if (($confine_to >= 0) && ($confine_to != $line_sec[$i])) { next; }
		print sprintf("%04d  %16s  %s\n",
			$i, category_name($line_category[$i]), $line_text[$i]);
	}
}

@ And the little routine which prints category names to |stdout|:

@c
sub category_name {
	my $cat = $_[0];
	if ($cat == $COMMENT_BODY_LCAT) { return "COMMENT_BODY"; }
	elsif ($cat == $MACRO_DEFINITION_LCAT) { return "MACRO_DEFINITION"; }
	elsif ($cat == $BAR_LCAT) { return "BAR"; }
	elsif ($cat == $INDEX_ENTRY_LCAT) { return "INDEX_ENTRY"; }
	elsif ($cat == $PURPOSE_LCAT) { return "PURPOSE"; }
	elsif ($cat == $INTERFACE_LCAT) { return "INTERFACE"; }
	elsif ($cat == $GRAMMAR_LCAT) { return "GRAMMAR"; }
	elsif ($cat == $DEFINITIONS_LCAT) { return "DEFINITIONS"; }
	elsif ($cat == $PARAGRAPH_START_LCAT) { return "PARAGRAPH_START"; }
	elsif ($cat == $BEGIN_VERBATIM_LCAT) { return "BEGIN_CODE"; }
	elsif ($cat == $TEXT_EXTRACT_LCAT) { return "TEXT_EXTRACT"; }
	elsif ($cat == $BEGIN_DEFINITION_LCAT) { return "BEGIN_DEFINITION"; }
	elsif ($cat == $GRAMMAR_BODY_LCAT) { return "GRAMMAR_BODY"; }
	elsif ($cat == $INTERFACE_BODY_LCAT) { return "INTERFACE_BODY"; }
	elsif ($cat == $CODE_BODY_LCAT) { return "CODE_BODY"; }
	elsif ($cat == $SOURCE_DISPLAY_LCAT) { return "SOURCE_DISPLAY"; }
	elsif ($cat == $TOGGLE_WEAVING_LCAT) { return "TOGGLE_WEAVING"; }
	elsif ($cat == $COMMAND_LCAT) { return "COMMAND"; }
	elsif ($cat == $CONT_DEFINITION_LCAT) { return "CONT_DEFINITION"; }
	else { return "? cat $cat"; }
}