filter fields in functions

mksrcinfo.sh

@@ -40,17 +40,18 @@ print_array_field() {
 }
 
 # load section content from its package function
+for field in "${section_fields[@]}"; do
+	_load_section_content_fields_pattern="$field|$_load_section_content_fields_pattern"
+done
 load_section_content() {
 	if [[ -n $1 ]]; then
 		suffix="_$1"
-	else
-		suffix=""
 	fi
 	if [[ ! "$(type -t "package$suffix")" = function ]]; then return; fi
 	# eval only variable assignments in package function
 	while read -r line; do
 		eval "$line"
-	done < <(declare -f "package$suffix" | grep -E '^[[:space:]]*(declare +)?[[:alnum:]_]*=')
+	done < <(declare -f "package$suffix" | grep -E "^[[:space:]]*(declare +)?($_load_section_content_fields_pattern)=" | sed 's/^[[:space:]]*(declare +)?//')
 }
 
 # print fields for a section