Added string literal to parser

entity/literal.go

@@ -1,6 +1,7 @@
 package entity
 
 import "fmt"
+import "unicode"
 import "github.com/alecthomas/participle/v2/lexer"
 
 // LiteralInt specifies an integer value. It can be assigned to any type that is
@@ -42,6 +43,46 @@ func (this *LiteralFloat) String () string {
 	return fmt.Sprint(this.Value)
 }
 
+// LiteralString specifies a string value. It takes on different data
+// representations depending on what the base type of what it is assigned to is
+// structurally equivalent to:
+//   - Integer: Single unicode code point. When assigning to an integer, the
+//     string literal may not be longer than one code point, and that code point
+//     must fit in the integer.
+//   - Slice of 8 bit integers: UTF-8 string.
+//   - Slice of 16 bit integers: UTF-16 string.
+//   - Slice of 32 bit (or larger) integers: UTF-32 string.
+//   - Array of integers: The same as slices of integers, but the string literal
+//     must fit inside of the array.
+//   - Byte pointer: Null-terminated UTF-8 string (AKA C-string).
+// A string literal cannot be directly assigned to an interface because it
+// contains no inherent type information. A value cast may be used for this
+// purpose.
+type LiteralString struct {
+	// Syntax
+	Pos lexer.Position
+	Value string `parser:" @String "`
+
+	// Semantics
+	Ty Type
+}
+func (*LiteralString) expression(){}
+func (*LiteralString) statement(){}
+func (this *LiteralString) Type () Type { return this.Ty }
+func (this *LiteralString) String () string {
+	out := "'"
+	for _, char := range this.Value {
+		if char == '\'' {
+			out += "\\'"
+		} else if unicode.IsPrint(char) {
+			out += string(char)
+		} else {
+			out += fmt.Sprintf("\\%03o", char)
+		}
+	}
+	return out + "'"
+}
+
 // LiteralArray is a composite array literal. It can contain any number of
 // values. It can be assigned to any array type that:
 //   1. has an identical length, and

lexer/lexer.go

@@ -149,9 +149,7 @@ func (this *fsplLexer) nextInternal () (token lexer.Token, err error) {
 		err = this.nextRune()
 		if err != nil { return }
 
-		println("NEW STRING")
 		for this.rune != '\'' {
-			println(string(this.rune))
 			if this.rune == '\\' {
 				var result rune
 				result, err = this.escapeSequence()

parser/parser_test.go

@@ -35,7 +35,8 @@ testString (test,
 [float]:F64 = 324.23409
 [boolean]:Bool = true
 [boolean2]:Bool = false
-[struct]:(x:Int y:(w:F64 z:F64)) = (x:1 y:(w:1.2 z:78.5))`,
+[struct]:(x:Int y:(w:F64 z:F64)) = (x:1 y:(w:1.2 z:78.5))
+[string]:String = 'hahah \'sup\005'`,
 // input
 `
 [int]:Int       = 5
@@ -43,6 +44,7 @@ testString (test,
 [boolean]:Bool  = true
 [boolean2]:Bool = false
 [struct]:(x:Int y:(w:F64 z:F64)) = (x: 1 y: (w: 1.2 z: 78.5))
+[string]:String = 'hahah \'sup\005'
 `)
 }
 

parser/tree.go

@@ -9,63 +9,64 @@ import flexer "git.tebibyte.media/sashakoshka/fspl/lexer"
 
 var parser = participle.MustBuild[Tree] (
 	participle.Union[entity.TopLevel] (
-		&entity.Function { },
-		&entity.Typedef  { },
-		&entity.Method   { }),
+		new(entity.Function),
+		new(entity.Typedef),
+		new(entity.Method)),
 	participle.Union[entity.Type] (
-		&entity.TypeNamed     { },
-		&entity.TypePointer   { },
-		&entity.TypeInterface { },
-		&entity.TypeStruct    { },
-		&entity.TypeArray     { },
-		&entity.TypeSlice     { }),
+		new(entity.TypeNamed),
+		new(entity.TypePointer),
+		new(entity.TypeInterface),
+		new(entity.TypeStruct),
+		new(entity.TypeArray),
+		new(entity.TypeSlice)),
 	participle.Union[entity.Expression] (
-		&entity.LiteralInt     { },
-		&entity.LiteralFloat   { },
-		&entity.LiteralArray   { },
-		&entity.LiteralStruct  { },
-		&entity.LiteralBoolean { },
-		&entity.Break          { },
-		&entity.Return         { },
-		&entity.IfElse         { },
-		&entity.Loop           { },
-		&entity.MethodCall     { },
-		&entity.MemberAccess   { },
-		&entity.Declaration    { },
-		&entity.Variable       { },
-		&entity.Subscript      { },
-		&entity.Slice          { },
-		&entity.Dereference    { },
-		&entity.Reference      { },
-		&entity.ValueCast      { },
-		&entity.BitCast        { },
-		&entity.Operation      { },
-		&entity.Call           { },
-		&entity.Block          { }),
+		new(entity.LiteralInt),
+		new(entity.LiteralFloat),
+		new(entity.LiteralString),
+		new(entity.LiteralArray),
+		new(entity.LiteralStruct),
+		new(entity.LiteralBoolean),
+		new(entity.Break),
+		new(entity.Return),
+		new(entity.IfElse),
+		new(entity.Loop),
+		new(entity.MethodCall),
+		new(entity.MemberAccess),
+		new(entity.Declaration),
+		new(entity.Variable),
+		new(entity.Subscript),
+		new(entity.Slice),
+		new(entity.Dereference),
+		new(entity.Reference),
+		new(entity.ValueCast),
+		new(entity.BitCast),
+		new(entity.Operation),
+		new(entity.Call),
+		new(entity.Block)),
 	participle.Union[entity.Statement] (
-		&entity.LiteralInt     { },
-		&entity.LiteralFloat   { },
-		&entity.LiteralArray   { },
-		&entity.LiteralStruct  { },
-		&entity.LiteralBoolean { },
-		&entity.Break          { },
-		&entity.Return         { },
-		&entity.Assignment     { },
-		&entity.IfElse         { },
-		&entity.Loop           { },
-		&entity.MethodCall     { },
-		&entity.MemberAccess   { },
-		&entity.Declaration    { },
-		&entity.Variable       { },
-		&entity.Subscript      { },
-		&entity.Slice          { },
-		&entity.Dereference    { },
-		&entity.Reference      { },
-		&entity.ValueCast      { },
-		&entity.BitCast        { },
-		&entity.Operation      { },
-		&entity.Call           { },
-		&entity.Block          { }),
+		new(entity.LiteralInt),
+		new(entity.LiteralFloat),
+		new(entity.LiteralArray),
+		new(entity.LiteralStruct),
+		new(entity.LiteralBoolean),
+		new(entity.Break),
+		new(entity.Return),
+		new(entity.Assignment),
+		new(entity.IfElse),
+		new(entity.Loop),
+		new(entity.MethodCall),
+		new(entity.MemberAccess),
+		new(entity.Declaration),
+		new(entity.Variable),
+		new(entity.Subscript),
+		new(entity.Slice),
+		new(entity.Dereference),
+		new(entity.Reference),
+		new(entity.ValueCast),
+		new(entity.BitCast),
+		new(entity.Operation),
+		new(entity.Call),
+		new(entity.Block)),
 	participle.UseLookahead(participle.MaxLookahead),
 	participle.Lexer(flexer.NewDefinition()))