Function relocation.

clause.go

@@ -200,7 +200,7 @@ func (q *sqlBuilder) insertParametrizedArgument(arg interface{}) {
 }
 
 func argToString(value interface{}) string {
-	if isNil(value) {
+	if utils.IsNil(value) {
 		return "NULL"
 	}
 

execution/execution.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"github.com/go-jet/jet/execution/internal"
+	"github.com/go-jet/jet/internal/utils"
 	"reflect"
 	"strconv"
 	"strings"
@@ -17,7 +18,7 @@ import (
 // Destination can be either pointer to struct or pointer to slice of structs.
 func Query(context context.Context, db DB, query string, args []interface{}, destinationPtr interface{}) error {
 
-	if destinationPtr == nil {
+	if utils.IsNil(destinationPtr) {
 		return errors.New("jet: Destination is nil")
 	}
 

insert_statement.go

@@ -5,6 +5,7 @@ import (
 	"database/sql"
 	"errors"
 	"github.com/go-jet/jet/execution"
+	"github.com/go-jet/jet/internal/utils"
 )
 
 // InsertStatement is interface for SQL INSERT statements
@@ -82,7 +83,7 @@ func (i *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
 	queryData.newLine()
 	queryData.writeString("INSERT INTO")
 
-	if isNil(i.table) {
+	if utils.IsNil(i.table) {
 		return "", nil, errors.New("jet: table is nil")
 	}
 

internal/utils/utils.go

@@ -6,6 +6,7 @@ import (
 	"go/format"
 	"os"
 	"path/filepath"
+	"reflect"
 	"strconv"
 	"strings"
 	"text/template"
@@ -154,3 +155,7 @@ func FormatTimestamp(t time.Time) []byte {
 	}
 	return b
 }
+
+func IsNil(v interface{}) bool {
+	return v == nil || (reflect.ValueOf(v).Kind() == reflect.Ptr && reflect.ValueOf(v).IsNil())
+}

table.go

@@ -2,6 +2,7 @@ package jet
 
 import (
 	"errors"
+	"github.com/go-jet/jet/internal/utils"
 )
 
 type table interface {
@@ -239,7 +240,7 @@ func (t *joinTable) serialize(statement statementType, out *sqlBuilder, options
 		return errors.New("jet: Join table is nil. ")
 	}
 
-	if isNil(t.lhs) {
+	if utils.IsNil(t.lhs) {
 		return errors.New("jet: left hand side of join operation is nil table")
 	}
 
@@ -262,7 +263,7 @@ func (t *joinTable) serialize(statement statementType, out *sqlBuilder, options
 		out.writeString("CROSS JOIN")
 	}
 
-	if isNil(t.rhs) {
+	if utils.IsNil(t.rhs) {
 		return errors.New("jet: right hand side of join operation is nil table")
 	}
 

update_statement.go

@@ -5,6 +5,7 @@ import (
 	"database/sql"
 	"errors"
 	"github.com/go-jet/jet/execution"
+	"github.com/go-jet/jet/internal/utils"
 )
 
 // UpdateStatement is interface of SQL UPDATE statement
@@ -62,7 +63,7 @@ func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error)
 	out.newLine()
 	out.writeString("UPDATE")
 
-	if isNil(u.table) {
+	if utils.IsNil(u.table) {
 		return "", nil, errors.New("jet: table to update is nil")
 	}
 

utils.go

@@ -124,10 +124,6 @@ func columnListToProjectionList(columns []Column) []projection {
 	return ret
 }
 
-func isNil(v interface{}) bool {
-	return v == nil || (reflect.ValueOf(v).Kind() == reflect.Ptr && reflect.ValueOf(v).IsNil())
-}
-
 func valueToClause(value interface{}) clause {
 	if clause, ok := value.(clause); ok {
 		return clause