Use bytes for highlight groups

cmd/micro/cellview.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"github.com/mattn/go-runewidth"
+	"github.com/zyedidia/micro/cmd/micro/highlight"
 	"github.com/zyedidia/tcell"
 )
 
@@ -20,7 +21,7 @@ func visualToCharPos(visualIndex int, lineN int, str string, buf *Buffer, tabsiz
 		width := StringWidth(str[:i], tabsize)
 
 		if group, ok := buf.Match(lineN)[charPos]; ok {
-			s := GetColor(group)
+			s := GetColor(highlight.GetGroup(group))
 			style = &s
 		}
 
@@ -108,7 +109,7 @@ func (c *CellView) Draw(buf *Buffer, top, height, left, width int) {
 				break
 			}
 			if group, ok := buf.Match(lineN)[colN]; ok {
-				curStyle = GetColor(group)
+				curStyle = GetColor(highlight.GetGroup(group))
 			}
 
 			char := line[colN]
@@ -164,7 +165,7 @@ func (c *CellView) Draw(buf *Buffer, top, height, left, width int) {
 
 		}
 		if group, ok := buf.Match(lineN)[len(line)]; ok {
-			curStyle = GetColor(group)
+			curStyle = GetColor(highlight.GetGroup(group))
 		}
 
 		// newline

cmd/micro/highlight/highlighter.go

@@ -8,7 +8,7 @@ import (
 func combineLineMatch(src, dst LineMatch) LineMatch {
 	for k, v := range src {
 		if g, ok := dst[k]; ok {
-			if g == "" {
+			if g == 0 {
 				dst[k] = v
 			}
 		} else {
@@ -38,7 +38,7 @@ func NewHighlighter(def *Def) *Highlighter {
 	return h
 }
 
-type LineMatch map[int]string
+type LineMatch map[int]uint8
 
 func FindIndex(regex *regexp.Regexp, str []byte, canMatchStart, canMatchEnd bool) []int {
 	regexStr := regex.String()
@@ -80,7 +80,7 @@ func (h *Highlighter) highlightRegion(start int, canMatchEnd bool, lineNum int,
 	loc := FindIndex(region.end, line, start == 0, canMatchEnd)
 	if loc != nil {
 		if region.parent == nil {
-			highlights[start+loc[1]] = ""
+			highlights[start+loc[1]] = 0
 			return combineLineMatch(highlights,
 				combineLineMatch(h.highlightRegion(start, false, lineNum, line[:loc[0]], region),
 					h.highlightEmptyRegion(start+loc[1], canMatchEnd, lineNum, line[loc[1]:])))
@@ -166,7 +166,7 @@ func (h *Highlighter) highlightEmptyRegion(start int, canMatchEnd bool, lineNum
 		for _, m := range matches {
 			highlights[start+m[0]] = p.group
 			if _, ok := highlights[start+m[1]]; !ok {
-				highlights[start+m[1]] = ""
+				highlights[start+m[1]] = 0
 			}
 		}
 	}

cmd/micro/highlight/parser.go

@@ -7,6 +7,18 @@ import (
 	"gopkg.in/yaml.v2"
 )
 
+var groups map[string]uint8
+var numGroups uint8
+
+func GetGroup(n uint8) string {
+	for k, v := range groups {
+		if v == n {
+			return k
+		}
+	}
+	return ""
+}
+
 // A Def is a full syntax definition for a language
 // It has a filetype, information about how to detect the filetype based
 // on filename or header (the first line of the file)
@@ -21,7 +33,7 @@ type Def struct {
 // It has a group that the rule belongs to, as well as
 // the regular expression to match the pattern
 type Pattern struct {
-	group string
+	group uint8
 	regex *regexp.Regexp
 }
 
@@ -39,13 +51,17 @@ type Rules struct {
 // region and also rules from the above region do not match inside this region
 // Note that a region may contain more regions
 type Region struct {
-	group  string
+	group  uint8
 	parent *Region
 	start  *regexp.Regexp
 	end    *regexp.Regexp
 	rules  *Rules
 }
 
+func init() {
+	groups = make(map[string]uint8)
+}
+
 // ParseDef parses an input syntax file into a highlight Def
 func ParseDef(input []byte) (s *Def, err error) {
 	// This is just so if we have an error, we can exit cleanly and return the parse error to the user
@@ -155,7 +171,13 @@ func parseRules(input []interface{}, curRegion *Region) (*Rules, error) {
 						return nil, err
 					}
 
-					rules.patterns = append(rules.patterns, &Pattern{group.(string), r})
+					groupStr := group.(string)
+					if _, ok := groups[groupStr]; !ok {
+						numGroups++
+						groups[groupStr] = numGroups
+					}
+					groupNum := groups[groupStr]
+					rules.patterns = append(rules.patterns, &Pattern{groupNum, r})
 				}
 			case map[interface{}]interface{}:
 				// Region
@@ -177,7 +199,12 @@ func parseRegion(group string, regionInfo map[interface{}]interface{}, prevRegio
 	var err error
 
 	region := new(Region)
-	region.group = group
+	if _, ok := groups[group]; !ok {
+		numGroups++
+		groups[group] = numGroups
+	}
+	groupNum := groups[group]
+	region.group = groupNum
 	region.parent = prevRegion
 
 	region.start, err = regexp.Compile(regionInfo["start"].(string))