lexer/numbers.go

@@ -4,21 +4,23 @@ import "github.com/sashakoshka/arf/file"
 
 // tokenizeSymbolBeginning lexes a token that starts with a number.
 func (lexer *LexingOperation) tokenizeNumberBeginning (negative bool) (err error) {
-	var number uint64
+	var number   uint64
+	var fragment float64
+	var isFloat  bool
 
 	if lexer.char == '0' {
 		lexer.nextRune()
 
 		if lexer.char == 'x' {
 			lexer.nextRune()
-			number, err = lexer.tokenizeNumber(16)
+			number, fragment, isFloat, err = lexer.tokenizeNumber(16)
 		} else if lexer.char == 'b' {
 			lexer.nextRune()
-			number, err = lexer.tokenizeNumber(2)
+			number, fragment, isFloat, err = lexer.tokenizeNumber(2)
 		} else if lexer.char == '.' {
-			number, err = lexer.tokenizeNumber(10)
+			number, fragment, isFloat, err = lexer.tokenizeNumber(10)
 		} else if lexer.char >= '0' && lexer.char <= '9' {
-			number, err = lexer.tokenizeNumber(8)
+			number, fragment, isFloat, err = lexer.tokenizeNumber(8)
 		} else {
 			return file.NewError (
 				lexer.file.Location(), 1,
@@ -26,19 +28,30 @@ func (lexer *LexingOperation) tokenizeNumberBeginning (negative bool) (err error
 				file.ErrorKindError)
 		}
 	} else {
-		number, err = lexer.tokenizeNumber(10)
+		number, fragment, isFloat, err = lexer.tokenizeNumber(10)
 	}
 
 	if err != nil { return }
 
 	token := Token { }
 
-	if negative {
-		token.kind  = TokenKindInt
-		token.value = int64(number) * -1
+	if isFloat {
+		floatNumber := float64(number) + fragment
+	
+		token.kind  = TokenKindFloat
+		if negative {
+			token.value = floatNumber * -1
+		} else {
+			token.value = floatNumber
+		}
 	} else {
-		token.kind  = TokenKindUInt
-		token.value = uint64(number)
+		if negative {
+			token.kind  = TokenKindInt
+			token.value = int64(number) * -1
+		} else {
+			token.kind  = TokenKindUInt
+			token.value = uint64(number)
+		}		
 	}
 	
 	lexer.addToken(token)
@@ -66,7 +79,14 @@ func runeToDigit (char rune, radix uint64) (digit uint64, worked bool) {
 }
 
 // tokenizeNumber reads and tokenizes a number with the specified radix.
-func (lexer *LexingOperation) tokenizeNumber (radix uint64) (number uint64, err error) {
+func (lexer *LexingOperation) tokenizeNumber (
+	radix uint64,
+) (
+	number   uint64,
+	fragment float64,
+	isFloat  bool,
+	err      error,
+) {
 	for {
 		digit, worked := runeToDigit(lexer.char, radix)
 		if !worked { break }
@@ -77,5 +97,25 @@ func (lexer *LexingOperation) tokenizeNumber (radix uint64) (number uint64, err
 		err = lexer.nextRune()
 		if err != nil { return }
 	}
+	
+	if lexer.char == '.' {
+		isFloat = true
+		err = lexer.nextRune()
+		if err != nil { return }
+
+		coef := 1 / float64(radix)
+		for {
+			digit, worked := runeToDigit(lexer.char, radix)
+			if !worked { break }
+
+			fragment += float64(digit) * coef
+			
+			coef /= float64(radix)
+
+			err = lexer.nextRune()
+			if err != nil { return }
+		}
+	}
+	
 	return
 }