Use u2016 for Vert

[bpiwowar]

See issue comment https://github.com/Khan/KaTeX/issues/286#issuecomment-118419984 : \Vert is associated with ∥ (u2225), which can be slanted or not, but should be with ‖ (u2016).

[khanbot]

Hey @bpiwowar,

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When you've done so, go ahead and comment [clabot:check] and I'll check again.

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[codecov]

Codecov Report

Merging #1427 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master    #1427   +/-   ##
=======================================
  Coverage   82.54%   82.54%           
=======================================
  Files          77       77           
  Lines        4388     4388           
  Branches      766      766           
=======================================
  Hits         3622     3622           
  Misses        664      664           
  Partials      102      102

Impacted Files	Coverage Δ
src/symbols.js	100% <100%> (ø)	⬆️

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[ronkok]

@bpiwowar, You make a strong case that U+2016 should be the Unicode code point used for \lVert. Unfortunately, the KaTeX fonts do not contain a glyph at code point U+2016. So the change you have proposed to symbols.js is insufficient by itself. As submitted, this will just cause KaTeX to issue a console warning that font metrics are unavailable for "‖", and then it will render a glyph from some system font, not the KaTeX fonts.

For this to be complete, one would have to change symbols.js, as you have done, and also add a glyph to the KaTeX_Main-Regular font in the KaTex font submodule.

[ronkok]

@bpiwowar, If your aim to make U+2016 effective as an input character, then you could write a macro:

defineMacro("\u2016", "\\Vert");

[ylemkimon]

Closing this as a won't fix. Please feel free to reopen or create a new pull request. Thank you for your contribution!