You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: parser.go
    path of file: ./repos/sqldef/database/postgres
    
    the code of the file until where you have to start completion: package postgres

import (
	"fmt"
	"strings"

	pgquery "github.com/pganalyze/pg_query_go/v4"
	"github.com/sqldef/sqldef/database"
	"github.com/sqldef/sqldef/parser"
)

type PostgresParser struct {
	parser  database.GenericParser
	
    
func shouldDeleteTypeCast(sourceNode *pgquery.Node, targetType parser.ColumnType) bool {
	switch sourceNode.Node.(type) {
	case *pgquery.Node_AConst:
		if targetType.Array {
			// Do not delete type cast from '{1,2,3}'::integer[]
			return false
		}
		// Delete type cast from '[0-9]'::text
		return true
	case *pgquery.Node_AArrayExpr, *pgquery.Node_TypeCast:
		// Delete type cast from ARRAY[1,2,3]::integer[]
		return true
	default:
		return false
	}
}