js or python

scratchieguy12345678

Comparing Python and Javascript is like comparing tomatoes to blueberries. Sure, they're both fruits, but they're both used for very different things.

Sheep_maker

@Greg8128 In JS there's a do expression proposal (stage 1) that aims to let you use statements as expressions; for example:

const val = do {
  if (condition) {
    const wow = a && b || c && d
    if (wow) {
      !a
    } else {
      b
    }
  } else {
    false
  }
}

which makes statements return whatever they would if they were eval'd (or run in the console)

Of course, it's not as elegant as in other programming languages, unfortunately.

gosoccerboy5 wrote:
Sheep_maker wrote:
Also, because Python variables are function scoped, it's not as inconvenient to store a value from an if-else or match statement as it is in JS with its block scoped let/const variables
OTOH, doesn't this make it a bit more convenient to use temporary variables in Javascript (and literally any other language with block scoping)? Also, does Python have IIFE's that would provide a construct for temporary variables? I'm just wondering
I guess del could be used for temporary variables

I think both languages' scoping are a good fit for themselves.

JavaScript is very asynchronous, so you might find yourself writing code with callbacks like

for (let i = 0; i < 10; i++) {
  setTimeout(() => {
    console.log(i)
  }, i * 100)
}

Had `let` instead been `var`, this would log “10” ten times, and back in the day, we'd have to use an IIFE to keep the value of `i` in each iteration of the loop. Now that `let` is blocked scope, this isn't a problem

Python is less likely to encounter these situations where an inner function references a variable from an outer function that is later changed because Python's “inner functions,” lambda expressions, are much more restricted. While you could instead define a function inside the loop, it's a lot harder to encounter situations in Python where you'd need callbacks like these. Even with Python's async/await, generally everything is written as if it should be executed in series, and executing something in parallel requires a bit more code (because running something async in parallel is usually a bug that often occurs in JS)

However, because Python's lambda expressions (and expressions in general) are very limited—probably because of their indentation-sensitive statement syntax—it's usually more convenient to take advantage of Python's function-scoped variables, like

if condition:
    temp_var = wow()
    value = temp_var * 2
else:
    value = 'b'
print(value)

In JS, you could just use an IIFE, though it's not very elegant; I agree with @Greg8128 that languages that unify statements and expressions are ideal

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PkmnQ

Greg8128 wrote:
gosoccerboy5 wrote:
Greg8128 wrote:
These languages didn't get in on the “statements as expressions” idea, and as a result JavaScript doesn't have it, either.
Please elaborate on the “statements as expressions” part, I don't quite understand
In most languages, statements (such as if/else and switch) are used to select which code to run. But in newer and cooler languages, they can be used to return a value. One such language is Scala:

In Scala, the if/else statement can be used as an expression, so a separate ternary operator is not needed.
val b = true
val i = if (b) 3 else 2
But there are also cooler applications. For example, the “match” expression is like a cooler version of the “switch” statement. Just like the if/else expression, it can be used to return a value.
val i = 2
val j = i match {
  case 1 => "one"
  case 2 => "two"
  case _ => "many"
}
This is pretty neat because it prevents you from needing to write “j = ” a bunch of times, and from needing to declare the variable j separately from assigning it.
Another thing you can do is use blocks as expressions:
val f = 3;
val i = {val j = 2; j * f + 3} // We only use j to calculate i
Think of it as a very simple closure that has no arguments and returns the last expression.

Overall, the point of being able to use statements as expressions is to be able to write in a more expressive style, with less boilerplate and a clearer relationship between the different calculations involved.

I might try out Scala.

This is an account that exists.

Here, have a useful link:

The Official List of Rejected Suggestions by Za-Chary

Raihan142857

Sheep_maker wrote:
@Greg8128 In JS there's a do expression proposal (stage 1) that aims to let you use statements as expressions; for example:
const val = do {
  if (condition) {
    const wow = a && b || c && d
    if (wow) {
      !a
    } else {
      b
    }
  } else {
    false
  }
}
which makes statements return whatever they would if they were eval'd (or run in the console)

Couldn't this conflict with do {} while() ?

I use scratch.
GF: I'll dump you. BF: hex dump or binary dump?

Greg8128

Raihan142857 wrote:
Sheep_maker wrote:
@Greg8128 In JS there's a do expression proposal (stage 1) that aims to let you use statements as expressions; for example:
const val = do {
  if (condition) {
    const wow = a && b || c && d
    if (wow) {
      !a
    } else {
      b
    }
  } else {
    false
  }
}
which makes statements return whatever they would if they were eval'd (or run in the console)
Couldn't this conflict with do {} while() ?

You can't use a do{} as a statement (the only place where you could use a do-while) so it doesn't matter. But honestly I think that the proposal is pretty ugly; the way it is done in Rust, Scala, etc, is much nicer.

My best projects:

Maximouse

gosoccerboy5 wrote:
I guess del could be used for temporary variables

In Python you just don't use temporary variables.

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gdpr5b78aa4361827f5c2a08d700

Maximouse wrote:
gosoccerboy5 wrote:
I guess del could be used for temporary variables
In Python you just don't use temporary variables.

Is that not extremely messy?

Maximouse

potatophant wrote:
Maximouse wrote:
gosoccerboy5 wrote:
I guess del could be used for temporary variables
In Python you just don't use temporary variables.
Is that not extremely messy?

Unless you write very long functions, no.

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gosoccerboy5

Maximouse wrote:
gosoccerboy5 wrote:
I guess del could be used for temporary variables
In Python you just don't use temporary variables.

Wait really? That's weird imo.

Maximouse

gosoccerboy5 wrote:
Maximouse wrote:
gosoccerboy5 wrote:
I guess del could be used for temporary variables
In Python you just don't use temporary variables.
Wait really? That's weird imo.

In Python this is valid:

for i in x:
  do_something_with(i)
print(i)

It doesn't cause problems but it's weird if you aren't used to it.

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gdpr5b78aa4361827f5c2a08d700

Maximouse wrote:
gosoccerboy5 wrote:
Maximouse wrote:
gosoccerboy5 wrote:
I guess del could be used for temporary variables
In Python you just don't use temporary variables.
Wait really? That's weird imo.
In Python this is valid:
for i in x:
  do_something_with(i)
print(i)
It doesn't cause problems but it's weird if you aren't used to it.

surely that's quite inefficient, memory management wise?

Maximouse

potatophant wrote:
surely that's quite inefficient, memory management wise?

If you keep functions short it isn't really a problem.

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gdpr5b78aa4361827f5c2a08d700

Maximouse wrote:
potatophant wrote:
surely that's quite inefficient, memory management wise?
If you keep functions short it isn't really a problem.

import 2tb from download-more.ram

Sikecon

Never learned Python loololololol

so I vote JavaScript. It's simple to learn (at least in the beginning―had a hard time figuring out OOP/OOD)

hi i love Fnf like very much
growing artist

gdpr5b78aa4361827f5c2a08d700

Both are fun to play with and are decent for small-scale things, but don't use either of them for anything serious unless you have to.

gosoccerboy5

potatophant wrote:
Maximouse wrote:
potatophant wrote:
surely that's quite inefficient, memory management wise?
If you keep functions short it isn't really a problem.
import 2tb from download-more.ram

Last edited by gosoccerboy5 (April 16, 2021 21:30:33)

PkmnQ

Maximouse wrote:
gosoccerboy5 wrote:
I guess del could be used for temporary variables
In Python you just don't use temporary variables.

Ok then why does this exist

with temp_var as "h"
  print(temp_var)

This is an account that exists.

Here, have a useful link:

The Official List of Rejected Suggestions by Za-Chary

Maximouse

PkmnQ wrote:
Ok then why does this exist
with temp_var as "h"
  print(temp_var)

For opening files and other things that need to be cleaned up after use.

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gosoccerboy5

gosoccerboy5 wrote:
Can we just appreciate Javascript's lambda at least

ninjaMAR

gosoccerboy5 wrote:
gosoccerboy5 wrote:
Can we just appreciate Javascript's lambda at least

stuff = lambda arg:stuff with arg

ninjamar.dev
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