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0 pointscma1y ago0 comments

Not being able to nest multiline lambdas into function arguments where they are called makes you have to read a lot of code backwards.

0 comments

kstrauser1y ago

I do wish it had lambdas. That's largely mitigated by the fact you can define functions pretty much anywhere. Instead of:

  def my_func():
      another_func(lambda: ...)

you can write

  def my_func():
      def inner(): ...
      another_func(inner)

Sure, it's creating a function, naming it, then immediately throwing it away, but gets the job done with minimal extra boilerplate.

cmaOP1y ago

That's what I meant by backwards though. Especially in UI OnClick code etc., I'd rather know the context that this happens on click of whichever object it is, but instead I have to write the clicked code before the code that registers it with the object, whose name has more relevant info, and then I end up having to name an extra thing too and keep the name in sync

kstrauser1y ago

But you can use a named function anywhere you'd use a lambda, in exactly the same way, just literally one line above where you'd pass the lambda to another function. It's not like you have to write the named function up at the top of the file. You can define it right there where it's going to be called. Truly, it's so easy and cheap to make a named function that I've never really missed having lambdas.

1 more reply

int_19h1y ago

One trick for this is to use the decorator syntax, e.g.:

   @foo.on_click
   def foo_clicked(): ...

Of course, for this, foo.on_click needs to be a callable function rather than a property.

sanderjd1y ago

Yep, I find python's lambda syntax to be probably its worst conceived feature. But just defining a named inner function works great for all the same use cases.

xigoi1y ago

That has nothing to do with significant indentation. Other languages with significant indentation (Nim, CoffeeScript) support multi-line function literals.

cb3211y ago

Because of Python's prominence and the divisiveness of significant indents, there is a large amount of misattribution of "whatever Python's syntax choices are" to "must be needed by significant indentation". E.g., whenever I go from Nim back to Python, I get annoyed that `t = 0; for e in x: t += e` is illegal in Python (Yes, I know `sum()` exists - it's just another easy syntax example to amplify your lambdas one.)

dgfitz1y ago

It also makes hard-to-maintain code. Trade-offs.

j / k navigate · click thread line to collapse

0 comments

kstrauser1y ago

I do wish it had lambdas. That's largely mitigated by the fact you can define functions pretty much anywhere. Instead of:

  def my_func():
      another_func(lambda: ...)

you can write

  def my_func():
      def inner(): ...
      another_func(inner)

Sure, it's creating a function, naming it, then immediately throwing it away, but gets the job done with minimal extra boilerplate.

cmaOP1y ago

kstrauser1y ago

1 more reply

int_19h1y ago

One trick for this is to use the decorator syntax, e.g.:

   @foo.on_click
   def foo_clicked(): ...

Of course, for this, foo.on_click needs to be a callable function rather than a property.

sanderjd1y ago

Yep, I find python's lambda syntax to be probably its worst conceived feature. But just defining a named inner function works great for all the same use cases.

xigoi1y ago

That has nothing to do with significant indentation. Other languages with significant indentation (Nim, CoffeeScript) support multi-line function literals.

cb3211y ago

dgfitz1y ago

It also makes hard-to-maintain code. Trade-offs.

j / k navigate · click thread line to collapse