From e60f6ae015309c68d3102e50fe19c8eb19dc7519 Mon Sep 17 00:00:00 2001
From: Brandon Dyck <brandon@dyck.us>
Date: Fri, 11 Apr 2025 19:03:45 -0600
Subject: [PATCH] Added Bracket, Where, and Token (without tests)

---
 bytes/bytes.go | 16 ++++++++++++++++
 gigaparsec.go  | 15 +++++++++++++++
 parser_test.go |  8 ++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 bytes/bytes.go

diff --git a/bytes/bytes.go b/bytes/bytes.go
new file mode 100644
index 0000000..79800e5
--- /dev/null
+++ b/bytes/bytes.go
@@ -0,0 +1,16 @@
+package bytes
+
+import (
+	"git.codemonkeysoftware.net/b/gigaparsec"
+)
+
+func Token[Out, WSOut any](whitespace gigaparsec.Parser[byte, WSOut]) func(p gigaparsec.Parser[byte, Out]) gigaparsec.Parser[byte, Out] {
+	mappedWS := gigaparsec.Map(whitespace, func(WSOut) struct{} { return struct{}{} })
+	var ignoreWS gigaparsec.Parser[byte, struct{}] = func(s gigaparsec.State[byte]) (gigaparsec.Result[byte, struct{}], error) {
+		result, err := mappedWS(s)
+		return result.Consume(false), err
+	}
+	return func(p gigaparsec.Parser[byte, Out]) gigaparsec.Parser[byte, Out] {
+		return gigaparsec.Seq2(p, gigaparsec.Repeat(0, ignoreWS), func(val Out, _ []struct{}) Out { return val })
+	}
+}
diff --git a/gigaparsec.go b/gigaparsec.go
index 0a2da77..30edffa 100644
--- a/gigaparsec.go
+++ b/gigaparsec.go
@@ -194,6 +194,17 @@ func (p Parser[In, Out]) Label(label string) Parser[In, Out] {
 	}
 }
 
+func (p Parser[In, Out]) Where(pred func(Out) bool) Parser[In, Out] {
+	return func(s State[In]) (Result[In, Out], error) {
+		result, err := p(s)
+		if result.success && !pred(result.value) {
+			result.success = false
+			result.message.got = "failed Where predicate"
+		}
+		return result, err
+	}
+}
+
 type ParseError Message
 
 func (pe ParseError) Error() string {
@@ -412,3 +423,7 @@ func Lazy[In, Out any](p func() Parser[In, Out]) Parser[In, Out] {
 		return p()(s)
 	}
 }
+
+func Bracket[In, Out, LOut, ROut any](left Parser[In, LOut], p Parser[In, Out], right Parser[In, ROut]) Parser[In, Out] {
+	return Seq3(left, p, right, func(_ LOut, val Out, _ ROut) Out { return val })
+}
diff --git a/parser_test.go b/parser_test.go
index 70708d0..388b64d 100644
--- a/parser_test.go
+++ b/parser_test.go
@@ -210,3 +210,11 @@ func TestRepeat(t *testing.T) {
 		test.False(t, succeeded)
 	})
 }
+
+func TestBracket(t *testing.T) {
+	Todo(t)
+}
+
+func TestWhere(t *testing.T) {
+	Todo(t)
+}