Added escape sequences

README.md

@@ -114,6 +114,7 @@ This is what generates expressions from tokens.
 - [x] Branches
 - [x] Loops
 - [x] Hexadecimal, octal and binary literals
+- [x] Escape sequences
 - [ ] Data structures
 - [ ] Type system
 - [ ] Type operator: `|` (`User | Error`)

examples/hello/hello.q

@@ -1,7 +1,7 @@
 import sys
 
 main() {
-	print("Hello", 5)
+	print("Hello\n", 6)
 }
 
 print(address, length) {

src/build/asm/Finalize.go

@@ -132,6 +132,12 @@ func (a Assembler) Finalize() ([]byte, []byte) {
 		case LABEL:
 			labels[x.Data.(*Label).Name] = Address(len(code))
 
+		case LOAD:
+			switch operands := x.Data.(type) {
+			case *MemoryRegister:
+				code = x64.LoadRegister(code, operands.Register, operands.Address.Offset, operands.Address.Length, operands.Address.Base)
+			}
+
 		case MODULO:
 			code = modulo(code, x.Data)
 

src/build/core/ExpressionToRegister.go

@@ -6,6 +6,7 @@ import (
 	"git.akyoto.dev/cli/q/src/build/cpu"
 	"git.akyoto.dev/cli/q/src/build/errors"
 	"git.akyoto.dev/cli/q/src/build/expression"
+	"git.akyoto.dev/cli/q/src/build/token"
 )
 
 // ExpressionToRegister puts the result of an expression into the specified register.
@@ -29,6 +30,13 @@ func (f *Function) ExpressionToRegister(node *expression.Expression, register cp
 		return err
 	}
 
+	if node.Token.Kind == token.Array {
+		array := f.VariableByName(node.Children[0].Token.Text(f.File.Bytes))
+		offset, err := f.Number(node.Children[1].Token)
+		f.MemoryRegister(asm.LOAD, asm.Memory{Base: array.Register, Offset: byte(offset), Length: 1}, register)
+		return err
+	}
+
 	if len(node.Children) == 1 {
 		if !node.Token.IsUnaryOperator() {
 			return errors.New(errors.MissingOperand, f.File, node.Token.End())

src/build/core/Number.go

@@ -35,7 +35,7 @@ func (f *Function) Number(t token.Token) (int, error) {
 
 	case token.Rune:
 		r := t.Bytes(f.File.Bytes)
-		r = r[1 : len(r)-1]
+		r = String(r)
 
 		if len(r) == 0 {
 			return 0, errors.New(errors.InvalidRune, f.File, t.Position+1)

src/build/core/String.go

@@ -0,0 +1,43 @@
+package core
+
+import "bytes"
+
+// String replaces the escape sequences in the contents of a string token with the respective characters.
+func String(data []byte) []byte {
+	data = data[1 : len(data)-1]
+	escape := bytes.IndexByte(data, '\\')
+
+	if escape == -1 {
+		return data
+	}
+
+	tmp := make([]byte, 0, len(data))
+
+	for {
+		tmp = append(tmp, data[:escape]...)
+
+		switch data[escape+1] {
+		case '0':
+			tmp = append(tmp, '\000')
+		case 't':
+			tmp = append(tmp, '\t')
+		case 'n':
+			tmp = append(tmp, '\n')
+		case 'r':
+			tmp = append(tmp, '\r')
+		case '"':
+			tmp = append(tmp, '"')
+		case '\'':
+			tmp = append(tmp, '\'')
+		case '\\':
+			tmp = append(tmp, '\\')
+		}
+
+		data = data[escape+2:]
+		escape = bytes.IndexByte(data, '\\')
+
+		if escape == -1 {
+			return tmp
+		}
+	}
+}

src/build/core/TokenToRegister.go

@@ -34,7 +34,8 @@ func (f *Function) TokenToRegister(t token.Token, register cpu.Register) error {
 		return nil
 
 	case token.String:
-		data := t.Bytes(f.File.Bytes)[1 : t.Length-1]
+		data := t.Bytes(f.File.Bytes)
+		data = String(data)
 		label := f.AddBytes(data)
 		f.RegisterLabel(asm.MOVE, register, label)
 		return nil

src/build/token/Tokenize.go

@@ -76,7 +76,7 @@ func Tokenize(buffer []byte) List {
 			i++
 
 			for i < Position(len(buffer)) {
-				if buffer[i] == limiter {
+				if buffer[i] == limiter && (buffer[i-1] != '\\' || buffer[i-2] == '\\') {
 					end = i + 1
 					i++
 					break

tests/examples_test.go

@@ -15,7 +15,7 @@ var examples = []struct {
 	Output   string
 	ExitCode int
 }{
-	{"hello", "", "Hello", 0},
+	{"hello", "", "Hello\n", 0},
 	{"factorial", "", "120", 0},
 	{"fibonacci", "", "55", 0},
 	{"gcd", "", "21", 0},

tests/programs/escape-rune.q

@@ -0,0 +1,9 @@
+main() {
+	assert '\0' == 0
+	assert '\t' == 9
+	assert '\n' == 10
+	assert '\r' == 13
+	assert '\"' == 34
+	assert '\'' == 39
+	assert '\\' == 92
+}

tests/programs/escape-string.q

@@ -0,0 +1,10 @@
+main() {
+	str := "\0\t\n\r\"\'\\"
+	assert str[0] == '\0'
+	assert str[1] == '\t'
+	assert str[2] == '\n'
+	assert str[3] == '\r'
+	assert str[4] == '\"'
+	assert str[5] == '\''
+	assert str[6] == '\\'
+}

tests/programs_test.go

@@ -24,11 +24,13 @@ var programs = []struct {
 	{"reassign", "", "", 0},
 	{"reuse", "", "", 0},
 	{"return", "", "", 0},
+	{"math", "", "", 0},
+	{"precedence", "", "", 0},
 	{"binary", "", "", 0},
 	{"octal", "", "", 0},
 	{"hexadecimal", "", "", 0},
-	{"math", "", "", 0},
+	{"escape-rune", "", "", 0},
-	{"precedence", "", "", 0},
+	{"escape-string", "", "", 0},
 	{"bitwise-and", "", "", 0},
 	{"bitwise-or", "", "", 0},
 	{"bitwise-xor", "", "", 0},