Set the lexer as a field on parser

goos: linux
goarch: amd64
pkg: roseh.moe/pkg/ccl
cpu: AMD Ryzen 9 5900X 12-Core Processor
         │ baseline.txt │              new.txt               │
         │    sec/op    │   sec/op     vs base               │
Parse-24    4.808µ ± 0%   4.739µ ± 0%  -1.44% (p=0.000 n=20)

1 files changed, 0 insertions, 4 deletions

diff --git a/lexer.go b/lexer.go
index 6561e38..a996451 100644
--- a/lexer.go
+++ b/lexer.go
@@ -113,7 +113,3 @@ func (l *lexer) next() (token, error) {
 	}
 	return token{}, l.error("invalid lexeme")
 }
-
-func newLexer(data []byte) *lexer {
-	return &lexer{data: data}
-}