On Mon, 16 Feb 2026 at 15:48, luigi scarso wrote:

On Sun, 15 Feb 2026 at 21:34, David Chiang wrote:

...

I see that part of my problem was creating glyph nodes with subtype 0 and I should use subtype 1 instead.

But to be clear, these are the cases I found surprising:

local a = node.new('glyph', 0) node.protect_glyph(a) node.protect_glyph(a) print(a.subtype) -- expected 256, actual 512 node.unprotect_glyph(a) node.unprotect_glyph(a) print(a.subtype) -- expected 0, actual 256

local b = node.new('disc') local c = node.new('glyph', 'character') b.replace = c node.unprotect_glyph(b) print(c.subtype) -- expected 1, actual 65281

The second case (expected 0, actual 256) is explained by what you wrote:

we make an exception for 256 which can be used when

...

no subtype is set which makes it possible to disable unprotection.

But the first case still seems surprising to me, and the third case really looks like a bug to me.

I will check them later.

Hans rewrote that part, see the commit https://svn.tug.org:8369/texlive?view=revision&revision=77938 -- luigi