Re: [PATCH] Use fontconfig spec for parsing font-weight.

[Yukio Siraichi]

> But 'semi-light' is already supported by Emacs, so why did you need to
> add the 'book' attribute?

I didn't really add the 'book' attribute. It was already there (as the last 
alias of 'semi-light'). I added a new row, and moved the 'semilight' aliases 
with it (left 'book' there, though). My guess is that, since it doesn't 
recognize the weight value (55) passed by 'fontconfig', it fallbacks to other 
weight values. So, what I did is to add a new weight value (the number that 
'fontconfig' converted to, from the OTF file).

> What happens if you do the above separately, that is with 2 calls
> instead of just one:
>
>  (set-face-attribute 'default nil :family "Cascadia Code")
>  (set-face-attribute 'default nil :weight 'semi-light)
>
> Does this work?

Apparently, not.