refactor

3 files changed, 59 insertions, 54 deletions

diff --git a/calculator.go b/calculator.go
index 3493382..b5dae10 100644
--- a/calculator.go
+++ b/calculator.go
@@ -1,27 +1,10 @@
 package main
 
 import (
-	"fmt"
-	"math"
 	"strconv"
 	"strings"
 )
 
-type Stack []float64
-
-func (s *Stack) push(v float64) {
-	*s = append(*s, v)
-}
-
-func (s *Stack) pop() *float64 {
-	if len(*s) > 0 {
-		v := (*s)[len(*s)-1]
-		*s = (*s)[:len(*s)-1]
-		return &v
-	}
-	return nil
-}
-
 type Calculator struct {
 	stack Stack
 	buf   string
@@ -79,40 +62,3 @@ func (c *Calculator) performOp(op byte) error {
 	c.buf = ""
 	return nil
 }
-
-// parseOp returns a closure that performs the specified arithmetic operation,
-// or OpError if op is not a valid operator.
-func parseOp(op byte) (func(lhs *float64, rhs float64), error) {
-	switch op {
-	case '+':
-		return func(lhs *float64, rhs float64) { *lhs += rhs }, nil
-	case '-':
-		return func(lhs *float64, rhs float64) { *lhs -= rhs }, nil
-	case '*':
-		return func(lhs *float64, rhs float64) { *lhs *= rhs }, nil
-	case '/':
-		return func(lhs *float64, rhs float64) {
-			if rhs != 0 {
-				*lhs /= rhs
-			}
-		}, nil
-	case '%':
-		return func(lhs *float64, rhs float64) {
-			if rhs != 0 {
-				*lhs = float64(int64(*lhs) % int64(rhs))
-			}
-		}, nil
-	case '^':
-		return func(lhs *float64, rhs float64) { *lhs = math.Pow(*lhs, rhs) }, nil
-	}
-	return nil, OpError{op}
-}
-
-// OpError records an invalid arithmetic operator.
-type OpError struct {
-	c byte
-}
-
-func (e OpError) Error() string {
-	return fmt.Sprintf("invalid operator: %c", e.c)
-}
diff --git a/op.go b/op.go
new file mode 100644
index 0000000..ab57a84
--- /dev/null
+++ b/op.go
@@ -0,0 +1,43 @@
+package main
+
+import (
+	"fmt"
+	"math"
+)
+
+// parseOp returns a closure that performs the specified arithmetic operation,
+// or OpError if op is not a valid operator.
+func parseOp(op byte) (func(lhs *float64, rhs float64), error) {
+	switch op {
+	case '+':
+		return func(lhs *float64, rhs float64) { *lhs += rhs }, nil
+	case '-':
+		return func(lhs *float64, rhs float64) { *lhs -= rhs }, nil
+	case '*':
+		return func(lhs *float64, rhs float64) { *lhs *= rhs }, nil
+	case '/':
+		return func(lhs *float64, rhs float64) {
+			if rhs != 0 {
+				*lhs /= rhs
+			}
+		}, nil
+	case '%':
+		return func(lhs *float64, rhs float64) {
+			if rhs != 0 {
+				*lhs = float64(int64(*lhs) % int64(rhs))
+			}
+		}, nil
+	case '^':
+		return func(lhs *float64, rhs float64) { *lhs = math.Pow(*lhs, rhs) }, nil
+	}
+	return nil, OpError{op}
+}
+
+// OpError records an invalid arithmetic operator.
+type OpError struct {
+	c byte
+}
+
+func (e OpError) Error() string {
+	return fmt.Sprintf("invalid operator: %c", e.c)
+}
diff --git a/stack.go b/stack.go
new file mode 100644
index 0000000..182d418
--- /dev/null
+++ b/stack.go
@@ -0,0 +1,16 @@
+package main
+
+type Stack []float64
+
+func (s *Stack) push(v float64) {
+	*s = append(*s, v)
+}
+
+func (s *Stack) pop() *float64 {
+	if len(*s) > 0 {
+		v := (*s)[len(*s)-1]
+		*s = (*s)[:len(*s)-1]
+		return &v
+	}
+	return nil
+}