surrealpatch/sql/let.go
2016-11-04 09:58:11 +00:00

60 lines
1.5 KiB
Go

// Copyright © 2016 Abcum Ltd
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package sql
func (p *parser) parseLetStatement() (stmt *LetStatement, err error) {
stmt = &LetStatement{}
stmt.KV = p.c.Get("KV").(string)
stmt.NS = p.c.Get("NS").(string)
stmt.DB = p.c.Get("DB").(string)
// The first part of a LET expression must
// always be an identifier, specifying a
// variable name to set.
_, stmt.Name, err = p.shouldBe(IDENT)
if err != nil {
return nil, err
}
// The next query part must always be a =
// operator, as this is a LET expression
// and not a binary expression.
_, _, err = p.shouldBe(EQ)
if err != nil {
return nil, err
}
// The next query part can be any expression
// including a parenthesised expression or a
// binary expression so handle accordingly.
stmt.What, err = p.parseExpr()
if err != nil {
return nil, err
}
// Check that we have reached the end of the
// statement with either a ';' or EOF.
if _, _, err = p.shouldBe(EOF, SEMICOLON); err != nil {
return nil, err
}
return
}