Function overloading in macros

[ristomatti]

@houmain Would it be a lot of work to support the same macro with varying amount of parameters? Example:

Hold = $0{150ms}
Hold = $0{mul[150, $1]ms}

The idea came from the fact I've found my macros Tap and Hold great ways to make the config more readable and to allow fine tuning the value for all the mappings in one place. But in a few situations I need the value to be longer, but I couldn't come up with a good name. It then occurred to me that using a multiplier would be a even better to have the value relative to the most often needed one.

Currently I've just used HoldX, but I remember having a similar need on some macros that execute commands earlier on. For instance it would be nice to have this

log = $(echo "$1" >> $LOG_FILE)
log = $(pastel --force-color paint "$1" "$0" >> $LOG_FILE)

...rather than this:

log = $(echo "$1" >> $LOG_FILE)
logColor = $(pastel --force-color paint "$1" "$0" >> $LOG_FILE)

What do you think?

[houmain]

Would it be a lot of work to support the same macro with varying amount of parameters?

Not only that, it would be against the design. It is currently allowed to redefine macros, like:

macro = X
A >> macro
macro = Y
B >> macro

So, it would be hard to distinguish between a redefinition and a definition of an overload.

I am thinking about adding a builtin macro default, which would return the second parameter when the first is empty. So this would work:

Hold = $0{mul[150, default[$1, 1]]ms}

I am still thinking about a nice solution for your second sample.

[ristomatti]

Perhaps %?

[ristomatti]

Related: https://www.quora.com/Is-the-number-sign-internationally-recognized-to-mean-number

[houmain]

I noticed some commits pushed, do you want me to give it a try it before a release?

Early feedback is always very welcome!

Could you reconsider using some other character than #?

I did not think about that. I just copied the syntax from shell scripts. But since # has indeed been problematic I changed it to $$ now.

[ristomatti]

Sorry to respond late rather than early, just haven't found the time earlier on. Both default and $$ work as expected. I also noticed you've added apply which seems brilliant. Great work once again!

I might have both time and inspiration update my config repo this evening. If I do, I will definitely include usages of both default and $$. I think there was also some mappings that could be simplified with apply. 🤔

Not only that, it would be against the design. It is currently allowed to redefine macros, like:

macro = X
A >> macro
macro = Y
B >> macro

I had missed the gist of this comment. Interesting! It hasn't occurred for me to test this earlier. I was under the impression the last definition would apply to the full config, but it's just the order in which they appear in the config that matters?

[houmain]

I might have both time and inspiration update my config repo this evening.

I am looking forward to see how you put them to good use!

but it's just the order in which they appear in the config that matters?

Yes, macros are immediately evaluated when a configuration line is parsed.

[ristomatti]

Both use cases can now be implemented thanks to the new default macro and the new special variable $$ introduced in version 4.9.0.

# "Hold" use case
Hold = $0{mul[130, default[$1, 1]]ms}

# "log" use case
switch = $0$1

_log1  = $(echo "$0" >> $LOG_FILE)
_log2  = $(pastel --force-color paint "$1" "$0" >> $LOG_FILE)

log    = switch["_log", $$]["$0", "$1"]