64 lines
1.5 KiB
Go
64 lines
1.5 KiB
Go
// Copyright © 2016 Abcum Ltd
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package sql
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func (p *parser) parseLetStatement() (stmt *LetStatement, err error) {
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grw := p.buf.rw
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p.buf.rw = false
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defer func() {
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p.buf.rw = grw
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}()
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stmt = &LetStatement{}
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// The first part of a LET expression must
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// always be an identifier, specifying a
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// variable name to set.
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stmt.Name, err = p.parseParam()
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if err != nil {
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return nil, err
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}
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// The next query part must always be a =
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// operator, as this is a LET expression
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// and not a binary expression.
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_, _, err = p.shouldBe(EQ)
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if err != nil {
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return nil, err
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}
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// The next query part can be any expression
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// including a parenthesised expression or a
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// binary expression so handle accordingly.
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stmt.What, err = p.parseExpr()
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if err != nil {
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return nil, err
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}
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// If this query has any subqueries which
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// need to alter the database then mark
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// this query as a writeable statement.
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stmt.RW = p.buf.rw
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return
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}
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