diff --git a/src/asm/Memory.go b/src/asm/Memory.go
index a183de6..1076405 100644
--- a/src/asm/Memory.go
+++ b/src/asm/Memory.go
@@ -3,6 +3,7 @@ package asm
 import (
 	"fmt"
 	"math"
+	"strconv"
 	"strings"
 
 	"git.akyoto.dev/cli/q/src/cpu"
@@ -31,12 +32,12 @@ func (mem *Memory) Format(custom string) string {
 			tmp.WriteString("+")
 		}
 
-		tmp.WriteString(fmt.Sprint(mem.Offset))
+		tmp.WriteString(strconv.Itoa(int(mem.Offset)))
 	}
 
 	tmp.WriteString("], ")
 	tmp.WriteString(custom)
 	tmp.WriteString(", ")
-	tmp.WriteString(fmt.Sprint(mem.Length))
+	tmp.WriteString(strconv.Itoa(int(mem.Length)))
 	return tmp.String()
 }
diff --git a/src/asm/MemoryNumber.go b/src/asm/MemoryNumber.go
index 651a20b..47c39d5 100644
--- a/src/asm/MemoryNumber.go
+++ b/src/asm/MemoryNumber.go
@@ -1,8 +1,6 @@
 package asm
 
-import (
-	"fmt"
-)
+import "strconv"
 
 // MemoryNumber operates with a memory address and a number.
 type MemoryNumber struct {
@@ -12,7 +10,7 @@ type MemoryNumber struct {
 
 // String returns a human readable version.
 func (data *MemoryNumber) String() string {
-	return data.Address.Format(fmt.Sprint(data.Number))
+	return data.Address.Format(strconv.Itoa(data.Number))
 }
 
 // MemoryNumber adds an instruction with a memory address and a number.
diff --git a/src/asm/Number.go b/src/asm/Number.go
index 768b232..3f0271c 100644
--- a/src/asm/Number.go
+++ b/src/asm/Number.go
@@ -1,7 +1,7 @@
 package asm
 
 import (
-	"fmt"
+	"strconv"
 )
 
 // Number operates with just a number.
@@ -11,7 +11,7 @@ type Number struct {
 
 // String returns a human readable version.
 func (data *Number) String() string {
-	return fmt.Sprintf("%d", data.Number)
+	return strconv.Itoa(data.Number)
 }
 
 // Number adds an instruction with a number.
diff --git a/src/asmc/call.go b/src/asmc/call.go
index 940c0da..cf84156 100644
--- a/src/asmc/call.go
+++ b/src/asmc/call.go
@@ -24,7 +24,7 @@ func (c *compiler) call(x asm.Instruction) {
 		}
 
 		distance := destination - (pointer.Position + Address(pointer.Size))
-		return Address(distance)
+		return distance
 	}
 
 	c.codePointers = append(c.codePointers, pointer)
diff --git a/src/asmc/jump.go b/src/asmc/jump.go
index e6d8f65..f01f547 100644
--- a/src/asmc/jump.go
+++ b/src/asmc/jump.go
@@ -40,7 +40,7 @@ func (c *compiler) jump(x asm.Instruction) {
 		}
 
 		distance := destination - (pointer.Position + Address(pointer.Size))
-		return Address(distance)
+		return distance
 	}
 
 	c.codePointers = append(c.codePointers, pointer)
diff --git a/src/asmc/resolvePointers.go b/src/asmc/resolvePointers.go
index 0dc879e..112a0d1 100644
--- a/src/asmc/resolvePointers.go
+++ b/src/asmc/resolvePointers.go
@@ -40,7 +40,7 @@ restart:
 			case 0xEB: // JMP
 				jump = []byte{0xE9}
 			default:
-				panic(fmt.Errorf("failed to increase pointer size for instruction 0x%x", opCode))
+				panic(fmt.Sprintf("failed to increase pointer size for instruction 0x%x", opCode))
 			}
 
 			pointer.Position += Address(len(jump) - int(pointer.OpSize))
@@ -90,9 +90,10 @@ restart:
 
 		for _, pointer := range c.dllPointers {
 			destination := importsStart + pointer.Resolve()
-			delta := destination - Address(c.codeStart+pointer.Position+Address(pointer.Size))
+			from := c.codeStart + pointer.Position + Address(pointer.Size)
+			offset := destination - from
 			slice := c.code[pointer.Position : pointer.Position+4]
-			binary.LittleEndian.PutUint32(slice, uint32(delta))
+			binary.LittleEndian.PutUint32(slice, uint32(offset))
 		}
 	}
 }
diff --git a/src/core/ArrayElementToRegister.go b/src/core/ArrayElementToRegister.go
index c623035..66777b9 100644
--- a/src/core/ArrayElementToRegister.go
+++ b/src/core/ArrayElementToRegister.go
@@ -29,7 +29,8 @@ func (f *Function) ArrayElementToRegister(node *expression.Expression, register
 		Length:         byte(1),
 	}
 
-	if index.Token.IsNumeric() {
+	switch {
+	case index.Token.IsNumeric():
 		offset, err := f.ToNumber(index.Token)
 
 		if err != nil {
@@ -38,7 +39,7 @@ func (f *Function) ArrayElementToRegister(node *expression.Expression, register
 
 		memory.Offset = int8(offset)
 
-	} else if index.Token.Kind == token.Identifier {
+	case index.Token.Kind == token.Identifier:
 		indexName := index.Token.Text(f.File.Bytes)
 		indexVariable := f.VariableByName(indexName)
 
@@ -53,7 +54,8 @@ func (f *Function) ArrayElementToRegister(node *expression.Expression, register
 		}
 
 		memory.OffsetRegister = indexVariable.Register
-	} else {
+
+	default:
 		typ, err := f.ExpressionToRegister(index, register)
 
 		if err != nil {
diff --git a/src/core/CompileDelete.go b/src/core/CompileDelete.go
index 6eae244..4792fb0 100644
--- a/src/core/CompileDelete.go
+++ b/src/core/CompileDelete.go
@@ -21,7 +21,7 @@ func (f *Function) CompileDelete(root *expression.Expression) error {
 	f.SaveRegister(f.CPU.Input[0])
 	f.SaveRegister(f.CPU.Input[1])
 	f.RegisterRegister(asm.MOVE, f.CPU.Input[0], variable.Register)
-	f.RegisterNumber(asm.MOVE, f.CPU.Input[1], int(variable.Type.(*types.Pointer).To.Size()))
+	f.RegisterNumber(asm.MOVE, f.CPU.Input[1], variable.Type.(*types.Pointer).To.Size())
 	f.CallSafe(f.Functions["mem.free"], f.CPU.Input[:2])
 	return nil
 }
diff --git a/src/core/ToNumber.go b/src/core/ToNumber.go
index da73904..1978939 100644
--- a/src/core/ToNumber.go
+++ b/src/core/ToNumber.go
@@ -13,30 +13,28 @@ import (
 func (f *Function) ToNumber(t token.Token) (int, error) {
 	switch t.Kind {
 	case token.Number:
-		digits := t.Text(f.File.Bytes)
+		var (
+			digits = t.Text(f.File.Bytes)
+			number int64
+			err    error
+		)
 
-		if strings.HasPrefix(digits, "0x") {
-			number, err := strconv.ParseInt(digits[2:], 16, 64)
-			return int(number), err
+		switch {
+		case strings.HasPrefix(digits, "0x"):
+			number, err = strconv.ParseInt(digits[2:], 16, 64)
+		case strings.HasPrefix(digits, "0o"):
+			number, err = strconv.ParseInt(digits[2:], 8, 64)
+		case strings.HasPrefix(digits, "0b"):
+			number, err = strconv.ParseInt(digits[2:], 2, 64)
+		default:
+			number, err = strconv.ParseInt(digits, 10, 64)
 		}
 
-		if strings.HasPrefix(digits, "0o") {
-			number, err := strconv.ParseInt(digits[2:], 8, 64)
-			return int(number), err
-		}
-
-		if strings.HasPrefix(digits, "0b") {
-			number, err := strconv.ParseInt(digits[2:], 2, 64)
-			return int(number), err
-		}
-
-		number, err := strconv.Atoi(digits)
-
 		if err != nil {
-			return 0, errors.New(err, f.File, t.Position)
+			return 0, errors.New(errors.InvalidNumber, f.File, t.Position)
 		}
 
-		return number, nil
+		return int(number), nil
 
 	case token.Rune:
 		r := t.Bytes(f.File.Bytes)
diff --git a/src/token/Tokenize_test.go b/src/token/Tokenize_test.go
index ab256cb..3ed541a 100644
--- a/src/token/Tokenize_test.go
+++ b/src/token/Tokenize_test.go
@@ -388,6 +388,21 @@ func TestLeadingZero(t *testing.T) {
 	}
 }
 
+func TestRange(t *testing.T) {
+	tokens := token.Tokenize([]byte("a..b"))
+
+	expected := []token.Kind{
+		token.Identifier,
+		token.Range,
+		token.Identifier,
+		token.EOF,
+	}
+
+	for i, kind := range expected {
+		assert.Equal(t, tokens[i].Kind, kind)
+	}
+}
+
 func TestSeparator(t *testing.T) {
 	tokens := token.Tokenize([]byte("a,b,c"))
 
diff --git a/src/types/Array.go b/src/types/Array.go
index fd6add2..b6629f0 100644
--- a/src/types/Array.go
+++ b/src/types/Array.go
@@ -1,7 +1,5 @@
 package types
 
-var String = &Array{Of: Int8}
-
 // Array is the address of an object.
 type Array struct {
 	Of Type
diff --git a/src/types/Common.go b/src/types/Common.go
index a846b61..87d5889 100644
--- a/src/types/Common.go
+++ b/src/types/Common.go
@@ -10,6 +10,7 @@ var (
 	Int8       = &Base{name: "int8", size: 1}
 	Float64    = &Base{name: "float64", size: 8}
 	Float32    = &Base{name: "float32", size: 4}
+	String     = &Array{Of: Int8}
 )
 
 var (