Refactored code structure

src/build/core/Execute.go

@@ -0,0 +1,69 @@
+package core
+
+import (
+	"strconv"
+
+	"git.akyoto.dev/cli/q/src/build/ast"
+	"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"
+)
+
+// Execute executes an operation on a register with a value operand.
+func (f *Function) Execute(operation token.Token, register cpu.Register, value *expression.Expression) error {
+	if value.IsLeaf() {
+		return f.ExecuteLeaf(operation, register, value.Token)
+	}
+
+	var temporary cpu.Register
+
+	if ast.IsFunctionCall(value) {
+		temporary = f.cpu.Return[0]
+	} else {
+		found := false
+		temporary, found = f.cpu.FindFree(f.cpu.General)
+
+		if !found {
+			panic("no free registers")
+		}
+	}
+
+	f.cpu.Use(temporary)
+	defer f.cpu.Free(temporary)
+	err := f.EvaluateTo(value, temporary)
+
+	if err != nil {
+		return err
+	}
+
+	return f.opRegisterRegister(operation, register, temporary)
+}
+
+// ExecuteLeaf performs an operation on a register with the given leaf operand.
+func (f *Function) ExecuteLeaf(operation token.Token, register cpu.Register, operand token.Token) error {
+	switch operand.Kind {
+	case token.Identifier:
+		name := operand.Text()
+		variable, exists := f.variables[name]
+
+		if !exists {
+			return errors.New(&errors.UnknownIdentifier{Name: name}, f.File, operand.Position)
+		}
+
+		defer f.useVariable(variable)
+		return f.opRegisterRegister(operation, register, variable.Register)
+
+	case token.Number:
+		value := operand.Text()
+		number, err := strconv.Atoi(value)
+
+		if err != nil {
+			return err
+		}
+
+		return f.opRegisterNumber(operation, register, number)
+	}
+
+	return errors.New(errors.NotImplemented, f.File, operation.Position)
+}