1277773 - Make keyword-value tables generic

Status: RESOLVED WONTFIX

(Core :: CSS Parsing and Computation, defect, P3)

Description

[Xidorn Quan [:xidorn] UTC+10]

To support using enum classes for CSS property enumerated value constants, it would be great if keyword tables could be generic, so that initializing/querying code could be cast-free.

In an ideal world, we should store keyword tables in two arrays, one for keywords, and the other for values, as described in bug 1277133 comment 1. But that may need to move the current code into some list file, and use a script to generate code from it, which isn't easy, and the benefits could be marginal.

An easier way could be, to make KTableEntry a generic struct but still use int16_t for storing the value. Then we do casting in the constructor and a value() method. (I know this is not completely cast-free, but you would at least no long need to write cast for each value). This looks like the simplest path.

I guess we may want to use constexpr for the constructor to ensure we do not encounter runtime static initialization, but that would need a C++11 level constexpr function support first. (I'm looking at you, MSVC2013)

Comment 1

[Xidorn Quan [:xidorn] UTC+10]

Attachment: prototype of my proposed idea

Comment 2

[Emilio Cobos Álvarez [:emilio]]

This is not really needed anymore.