Aetherus
Why is `Kernel.then/2` defined as a macro?
Just out of curiosity. Why is Kernel.then/2 a macro instead of a normal function?
Here’s the source code of Kernel.then/2:
defmacro then(value, fun) do
quote do
unquote(fun).(unquote(value))
end
end
Here’s what I thought what the source code of Kernel.then/2 could be:
def then(value, fun) do
fun.(value)
end
Marked As Solved
benwilson512
To be a comparable case you need to use theni from another module. As I recall inlining can work differently depending on whether you are inlining a function within the same module or from another module.
Also Liked
adamu
Check out the pull request that did it. It includes reasons and a link to a mailing list discussion, too.
Aetherus
You are absolutely correct. Thank you.
When I put the callers and the callees into different modules, theni/2 generates the same instructions as thenf/2.
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