Today I was surprised by how "with" will spring a variable into existence permanently (texmacs 2.1.2 pre-compiled deb for ubuntu focal).
What do you think this will do?
<if|<provides|dummy>|dummy exists <value|dummy>>
<with|dummy|temp-value|<if|<provides|dummy>|dummy briefly exists <value|dummy>>>
<if|<provides|dummy>|dummy finally exists <value|dummy>>
dummy briefly exists temp-value
dummy finally exists ? <--- this line shouldn't exist
Yep - after using a <with|var|...
the var is now provided for globally -- with label uninit.
This means the <provides| test is weakened and existing macros can be broken by other macros.
Sam