string: make left/right private

vlib/builtin/string.v

@@ -384,14 +384,14 @@ pub fn (s string) split_into_lines() []string {
 }
 
 // 'hello'.left(2) => 'he'
-pub fn (s string) left(n int) string {
+fn (s string) left(n int) string {
 	if n >= s.len {
 		return s
 	}
 	return s.substr(0, n)
 }
 // 'hello'.right(2) => 'llo'
-pub fn (s string) right(n int) string {
+fn (s string) right(n int) string {
 	if n >= s.len {
 		return ''
 	}

vlib/compiler/fn.v

@@ -214,7 +214,7 @@ fn (p mut Parser) fn_decl() {
 		is_public: is_pub || p.is_vh // functions defined in .vh are always public
 		is_unsafe: p.attr == 'unsafe_fn'
 		is_deprecated: p.attr == 'deprecated'
-		comptime_define: if p.attr.starts_with('if ') { p.attr.right(3) } else { '' }
+		comptime_define: if p.attr.starts_with('if ') { p.attr[3..] } else { '' }
 	}
 	is_live := p.attr == 'live' && !p.pref.is_so  && p.pref.is_live
 	if p.attr == 'live' &&  p.first_pass() && !p.pref.is_live && !p.pref.is_so {

vlib/compiler/parser.v

@@ -2093,7 +2093,7 @@ fn (p mut Parser) index_expr(typ_ string, fn_ph int) string {
 		// }
 		if is_indexer {
 			l := p.cgen.cur_line.trim_space()
-			index_val := l.right(l.last_index(' ')).trim_space()
+			index_val := l[l.last_index(' ')..].trim_space()
 			p.cgen.resetln(l[..fn_ph])
 			p.table.varg_access << VargAccess{
 				fn_name: p.cur_fn.name,

vlib/time/time.v

@@ -527,7 +527,7 @@ pub fn (t Time) get_fmt_date_str(fmt_dlmtr FormatDelimiter, fmt_date FormatDate)
         }
 
         month := '${t.smonth()}'
-        year := t.year.str().right(2)
+        year := t.year.str()[2..]
 
         return  match fmt_date {
                         .ddmmyy     { '${t.day:02d}|${t.month:02d}|$year' }