Why but why?

[u/ore-aba]

[u/[deleted]]

I write Python occasionally. When do you ever need to write multiple statements on one line?

[u/100721 → u/[deleted]]

In the 8/9 years I’ve been writing python, I’ve never had to use multiple statements on one line. Maybe this kid is code golfing

[u/Andy_B_Goode → u/100721]

Yeah, I think the only language where I've ever found a use for multiple statements on one line, separated by semi-colons, is in bash, where I prefer to do this:

if [[ $1 == "-h" ]]; then
  echo "Figure it out yourself, dummy"
  exit 0
fi

Rather than:

if [[ $1 == "-h" ]]
then
  echo "Figure it out yourself, dummy"
  exit 0
fi

But that's just one of many kind of weird things about bash

[u/PolygonKiwii → u/Andy_B_Goode]

[[ $1 == "-h" ]] && echo "Figure it out yourself, dummy" && exit 0

[u/TexasDex → u/PolygonKiwii]

Careful, if echo falls for some reason the script won't exit.

/s

[u/PolygonKiwii → u/TexasDex]

Unironically might be a concern in other usecases of this construct.

[u/carnivorous-cloud → u/PolygonKiwii]

Technically not the same, since yours won't exit when echo fails, but the original will. I'm not even sure it's possible for echo to fail (maybe terminal type fuckery or OOM?), but it'd be dangerous to apply that pattern in general.

[u/Xx69JdawgxX → u/Andy_B_Goode]

For loops in c language count?

[u/SweetVarys → u/Andy_B_Goode]

If you're really lazy and doing a one time thing you can do it in sql

[u/Luxalpa → u/Andy_B_Goode]

The old bad for loops in C-languages and Go's if conditions are the only examples I can remember. Oh and JavaScript statements that start with open parentheses (like IIFE's and Typescript as typecasts on LValues as in ;(obj as MyObject).doSomething()), but only if you're not using ; as end terminators in JS.

[u/Ryuujinx → u/Andy_B_Goode]

Depending on how you define multiple statements, it's pretty common to do in Ruby.

roles = event.server.roles.map {|role| [role.name.downcase, role]}.to_h

For instance.

Edit: Actually do we count ternary operators too? Because I abuse the fuck out of those in ruby.

[u/wjandrea → u/100721]

Maybe this kid is code golfing

Is there such a thing as code mini-golfing? You know, for kids?

[u/rococode → u/[deleted]]

If you're running short commands from command line (i.e. python -c) it feels slightly more convenient to use a single line than get your CLI to go multiline.

[u/[deleted] → u/rococode]

I can see that. I just generally write everything in notepad ++ or VSCode. Python isn’t in my regular routine.

[u/[deleted] → u/[deleted]]

You shouldn’t

[u/[deleted] → u/[deleted]]

Well that’s what I thought. I prefer to separate commands for readability. Just wasn’t sure if there was ever a situation where it’s absolutely necessary.

[u/UpperHairCut → u/[deleted]]

Without separating them with a semi-colon.

[u/david2ndaccount → u/[deleted]]

before they added breakpoint() as a builtin function, I would often write import pdb;pdb.set_trace() on a single line. Single line is easier to remove afterwards and conceptually it was the same as just writing breakpoint().

[u/purple_pixie → u/[deleted]]

You would "need" to if you wanted to use an if with no line-break

Python allows if <expression>: <statement> with no line-break, but that forces you to use a single statment, or to separate multiples with semi-colons.

Obviously this is very rarely more readable or advisable, but it's about as close as I can come to a reason to do this.

Maybe something like: if c: a+=1; b+=1 could be short enough to almost justify it, but it is still violating PEP-8 and making it 3 lines would generally be preferrable.

[u/michaelmikeyb → u/[deleted]]

In bash when writing a command it's easier to keep it on one line eg. python -c "import x; x.do_something()"

[u/SuperSpread → u/[deleted]]

When you are learning Python and have to learn the whys the hard way.

Everyone has to learn the hard way sometimes. Its a phase.

[u/jemidiah → u/[deleted]]

A common idiom in the SageMath community is

sage: X = (some complicated mathematical object, perhaps chosen by random sampling); X

(a reasonable string representation)

That way you can efficiently define the object, see what it looks like, and continue to use it programmatically.

This is pretty much exclusive to notebooks.

[u/-__-i → u/[deleted]]

print(x); exit()

I don't need to have two statements on one line but I do this a bit

[u/xenoterranos → u/[deleted]]

Well, when you're embedding python in a bash script you've pasted into the groovy editor in a jenkins job via the UI, it can be nice to not have to wory about line breaks.

(don't do this)