[CALCITE-4238] Create a default parser configuration, to reduce redundant information in sub-parsers

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.26.0
• Labels: pull-request-available
• Assignee: Julian Hyde
• Reporter: Julian Hyde
• Created: 08/Sep/20 18:22
• Updated: 06/Oct/20 17:16
• Resolved: 29/Sep/20 20:17

Description

Create a default parser configuration, to reduce redundant information in sub-parsers. In particular, each sub-project parser would not need its own list of non-reserved keywords (currently the list is over 250 keywords, and the list is identical in each sub-parser).

Since CALCITE-2405 each sub-parser has its own list of non-reserved keywords. This is good, because it allows the sub-parser to make keywords non-reserved (e.g. in DRILL-1065 Drill wanted EXEC to be non-reserved) but it still requires each parser to have a list of non-reserved keywords (see e.g. the list in Babel parser). And if we add a keyword to Calcite, we almost always have to modify the list in each sub-parser.

This proposal would move the list of default non-reserved keywords to a shared config file. This would reduce the amount of code in sub-parsers, and remove the need to edit them when we add a keyword to the base parser.

Also, we would not need to modify each sub-parser each time we add a markup variable (e.g. when we added binaryOperatorsTokens and extraBinaryExpressions in CALCITE-2843).

Issue Links

• relates to: CALCITE-2405 In Babel parser: allow to use some reserved keyword as identifier
• links to: GitHub Pull Request #2167