Remove unused cast interface.

mysql/cast.go

@@ -5,66 +5,40 @@ import (
 	"strconv"
 )
 
-type cast interface {
-	// AS casts expressions as castType type
-	AS(castType string) Expression
-	// AS_CHAR casts expression as char with optional length
-	AS_CHAR(length ...int) StringExpression
-	// AS_DATE casts expression AS date type
-	AS_DATE() DateExpression
-	// AS_FLOAT casts expressions as float type
-	AS_FLOAT() FloatExpression
-	// AS_DOUBLE casts expressions as double type
-	AS_DOUBLE() FloatExpression
-	// AS_DECIMAL casts expression AS numeric type
-	AS_DECIMAL() FloatExpression
-	// AS_TIME casts expression AS time type
-	AS_TIME() TimeExpression
-	// AS_DATETIME casts expression as datetime type
-	AS_DATETIME() DateTimeExpression
-	// AS_SIGNED casts expressions as signed integer type
-	AS_SIGNED() IntegerExpression
-	// AS_UNSIGNED casts expression as unsigned integer type
-	AS_UNSIGNED() IntegerExpression
-	// AS_BINARY casts expression as binary type
-	AS_BINARY() StringExpression
-}
-
-type castImpl struct {
+type cast struct {
 	jet.Cast
 }
 
 // CAST function converts a expr (of any type) into latter specified datatype.
-func CAST(expr Expression) cast {
-	castImpl := &castImpl{}
+func CAST(expr Expression) *cast {
+	ret := &cast{}
+	ret.Cast = jet.NewCastImpl(expr)
 
-	castImpl.Cast = jet.NewCastImpl(expr)
-
-	return castImpl
+	return ret
 }
 
 // AS casts expressions to castType
-func (c *castImpl) AS(castType string) Expression {
+func (c *cast) AS(castType string) Expression {
 	return c.Cast.AS(castType)
 }
 
 // AS_DATETIME cast expression to DATETIME type
-func (c *castImpl) AS_DATETIME() DateTimeExpression {
+func (c *cast) AS_DATETIME() DateTimeExpression {
 	return DateTimeExp(c.AS("DATETIME"))
 }
 
 // AS_SIGNED casts expression to SIGNED type
-func (c *castImpl) AS_SIGNED() IntegerExpression {
+func (c *cast) AS_SIGNED() IntegerExpression {
 	return IntExp(c.AS("SIGNED"))
 }
 
 // AS_UNSIGNED casts expression to UNSIGNED type
-func (c *castImpl) AS_UNSIGNED() IntegerExpression {
+func (c *cast) AS_UNSIGNED() IntegerExpression {
 	return IntExp(c.AS("UNSIGNED"))
 }
 
 // AS_CHAR casts expression to CHAR type with optional length
-func (c *castImpl) AS_CHAR(length ...int) StringExpression {
+func (c *cast) AS_CHAR(length ...int) StringExpression {
 	if len(length) > 0 {
 		return StringExp(c.AS("CHAR(" + strconv.Itoa(length[0]) + ")"))
 	}
@@ -73,29 +47,29 @@ func (c *castImpl) AS_CHAR(length ...int) StringExpression {
 }
 
 // AS_DATE casts expression AS DATE type
-func (c *castImpl) AS_DATE() DateExpression {
+func (c *cast) AS_DATE() DateExpression {
 	return DateExp(c.AS("DATE"))
 }
 
-func (c *castImpl) AS_FLOAT() FloatExpression {
+func (c *cast) AS_FLOAT() FloatExpression {
 	return FloatExp(c.AS("FLOAT"))
 }
 
-func (c *castImpl) AS_DOUBLE() FloatExpression {
+func (c *cast) AS_DOUBLE() FloatExpression {
 	return FloatExp(c.AS("DOUBLE"))
 }
 
 // AS_DECIMAL casts expression AS DECIMAL type
-func (c *castImpl) AS_DECIMAL() FloatExpression {
+func (c *cast) AS_DECIMAL() FloatExpression {
 	return FloatExp(c.AS("DECIMAL"))
 }
 
 // AS_TIME casts expression AS TIME type
-func (c *castImpl) AS_TIME() TimeExpression {
+func (c *cast) AS_TIME() TimeExpression {
 	return TimeExp(c.AS("TIME"))
 }
 
 // AS_BINARY casts expression as BINARY type
-func (c *castImpl) AS_BINARY() StringExpression {
+func (c *cast) AS_BINARY() StringExpression {
 	return StringExp(c.AS("BINARY"))
 }