Cleanup a random bunch of repetitive loops

Replace them with helper function calls.

block.go

@@ -196,11 +196,8 @@ func (p *parser) prefixHeader(out *bytes.Buffer, data []byte) int {
 	for level < 6 && data[level] == '#' {
 		level++
 	}
-	i, end := 0, 0
-	for i = level; data[i] == ' '; i++ {
-	}
-	for end = i; data[end] != '\n'; end++ {
-	}
+	i := skipChar(data, level, ' ')
+	end := skipUntilChar(data, i, '\n')
 	skip := end
 	id := ""
 	if p.flags&EXTENSION_HEADER_IDS != 0 {
@@ -245,13 +242,8 @@ func (p *parser) prefixHeader(out *bytes.Buffer, data []byte) int {
 func (p *parser) isUnderlinedHeader(data []byte) int {
 	// test of level 1 header
 	if data[0] == '=' {
-		i := 1
-		for data[i] == '=' {
-			i++
-		}
-		for data[i] == ' ' {
-			i++
-		}
+		i := skipChar(data, 1, '=')
+		i = skipChar(data, i, ' ')
 		if data[i] == '\n' {
 			return 1
 		} else {
@@ -261,13 +253,8 @@ func (p *parser) isUnderlinedHeader(data []byte) int {
 
 	// test of level 2 header
 	if data[0] == '-' {
-		i := 1
-		for data[i] == '-' {
-			i++
-		}
-		for data[i] == ' ' {
-			i++
-		}
+		i := skipChar(data, 1, '-')
+		i = skipChar(data, i, ' ')
 		if data[i] == '\n' {
 			return 2
 		} else {
@@ -596,10 +583,7 @@ func (p *parser) isFencedCode(data []byte, syntax **string, oldmarker string) (s
 
 	if syntax != nil {
 		syn := 0
-
-		for i < len(data) && data[i] == ' ' {
-			i++
-		}
+		i = skipChar(data, i, ' ')
 
 		if i >= len(data) {
 			return
@@ -643,9 +627,7 @@ func (p *parser) isFencedCode(data []byte, syntax **string, oldmarker string) (s
 		*syntax = &language
 	}
 
-	for i < len(data) && data[i] == ' ' {
-		i++
-	}
+	i = skipChar(data, i, ' ')
 	if i >= len(data) || data[i] != '\n' {
 		return
 	}
@@ -674,11 +656,7 @@ func (p *parser) fencedCode(out *bytes.Buffer, data []byte, doRender bool) int {
 		}
 
 		// copy the current line
-		end := beg
-		for end < len(data) && data[end] != '\n' {
-			end++
-		}
-		end++
+		end := skipUntilChar(data, beg, '\n') + 1
 
 		// did we reach the end of the buffer without a closing marker?
 		if end >= len(data) {
@@ -781,9 +759,7 @@ func (p *parser) tableHeader(out *bytes.Buffer, data []byte) (size int, columns
 	if data[i] == '|' && !isBackslashEscaped(data, i) {
 		i++
 	}
-	for data[i] == ' ' {
-		i++
-	}
+	i = skipChar(data, i, ' ')
 
 	// each column header is of form: / *:?-+:? *|/ with # dashes + # colons >= 3
 	// and trailing | optional on last column

html.go

@@ -867,6 +867,14 @@ func skipSpace(tag []byte, i int) int {
 	return i
 }
 
+func skipChar(data []byte, start int, char byte) int {
+	i := start
+	for i < len(data) && data[i] == char {
+		i++
+	}
+	return i
+}
+
 func doubleSpace(out *bytes.Buffer) {
 	if out.Len() > 0 {
 		out.WriteByte('\n')