func (w *Wrapper) IsNullable() bool {
	if w.inner == nil {
		return true
	}
	return w.inner.IsNullable()
}
IsNullable implements sql.Expression
package expression
import (
	"fmt"
	"github.com/dolthub/go-mysql-server/sql"
)
type Wrapper struct {
	inner sql.Expression
}
var _ sql.Expression = (*Wrapper)(nil)
func WrapExpression(expr sql.Expression) *Wrapper {
	return &Wrapper{expr}
}
func WrapExpressions(exprs ...sql.Expression) []sql.Expression {
	wrappers := make([]sql.Expression, len(exprs))
	for i, expr := range exprs {
		wrappers[i] = WrapExpression(expr)
	}
	return wrappers
}
func (w *Wrapper) Children() []sql.Expression {
	if w.inner == nil {
		return nil
	}
	return []sql.Expression{w.inner}
}
func (w *Wrapper) Eval(ctx *sql.Context, row sql.Row) (interface{}, error) {
	if w.inner == nil {
		return nil, nil
	}
	return w.inner.Eval(ctx, row)
}