The goal is to catch cases where the return value exists, but is
forgotten. There was a large enough number of them to turn this
into a real check. Initially, I just wanted to implement it to fix
the problems, then delete the code. But since this is so common, I
think it is worth the annoyance.
Currently, emit_signal always call all connected function. However,
it is very wasteful for some I/O intensive operations like icon
lookup. This commit adds a trick (private API) to stop once
a condition is met.
It will also in the future be used for the permission system, but
this is not yet implementd.
This way their name doesn't get mangle by the broken magic. It will also
eventually allow to `error()` in the template when the implicit
`@function` is used.
This commit also fixes a large number of issues found while
proof-reading everything.
It does not provide much value. The version number is already known to
ldoc globally in the "description" variable.
Signed-off-by: Uli Schlachter <psychon@znc.in>
The requirement to call add_signal() was added to catch typos. However, this
requirement became increasingly annoying with property::<name> signals and e.g.
gears.object allowing arbitrary properties to be changed.
All of this ended up in a single commit because tests/examples fails if I first
let add_signal() emit a deprecation warning.
Signed-off-by: Uli Schlachter <psychon@znc.in>
Similar systems already exist un luaobject, wibox and the declarative
widget system. This close the gap and also bring the property based
syntax to wibox and other gears.object users.
While this need to be enabled explicitly for legacy reasons, it
doesn't break the API.
Once widespread, this implementation will replace the one found
in wibox.widget.base_widget.
Lua will remove objects as values from a weak table before these objects are
finalized, but as values only in the next garbage collection cycle after the
object was finalized. Up to now, gears.object uses a table with weak keys so
that :disconnect_signal() works. This means that a signal can still call methods
which were already considered garbage by the garbage collector and thus can use
userdata from the C side which was already finalized. Crashes and other bugs
result.
This commit changes the code so that the function is also a value in the weak
table. Thus, the GC will remove the entry before the object is finalized.
Special magic is needed for Lua 5.1, because there only userdata has the
behavior that we want while we have a function. We do some magic with function
environments to make this work...
Closes https://github.com/awesomeWM/awesome/pull/567.
Signed-off-by: Uli Schlachter <psychon@znc.in>
Connecting to a signal weakly has the same effect as connecting to it strongly,
but it allows the garbage collector to disconnect the signal in case nothing
else references this function.
Signed-off-by: Uli Schlachter <psychon@znc.in>
Peter Anderson
Emmanuel Lepage Vallee
Aire-One
Kevin Zander
Uli Schlachter
Uli Schlachter
Daniel Hahler
Julian Wollrath