Symbolic Butt posted:

code:

irb(main):001:0> 1/2+3
=> 3
irb(main):002:0> 1./2.+3
=> 0

fritz posted:

what language is that i want to avoid it

Brain Candy posted:

stack allocation, operator overloading and vectorization are a thing, but IDK, the winner for math isn't c++/c.

surprise, it's fortran and OpenCL/CUDA. most of the 'fast' c/c++ libraries are wrappers.

JewKiller 3000 posted:

if you can't define the function swap so that the assert passes, your language does not have pass by reference

fritz posted:

what language is that i want to avoid it

FamDav posted:

You can write a swap for non-primitives in java

EDIT: which jives totes mcgotes with your statement, but still

Notorious b.s.d. posted:

nope you can't

the references you change will only be your local ones, because java is always pass by value at all times.

c# permits pass by name ("out" parameters), but java does not

Nomnom Cookie posted:

I dunno why you're using the term pass by reference then. It has a clear meaning and deals with language semantics, not calling conventions.

quote:

Taking your meaning, which is "everything is a pointer", it's not an actual issue. Dereferencing pointers from L1 is basically free.

quote:

Bro you need to learn more about JVM internals if you want to poo poo on them. For starters, Hotspot allocates out of a thread-local buffer (imaginatively acronym'ed as TLAB). In the vast majority of cases Java allocations are pointer bumps.

Zlodo posted:

of course like everything it only becomes an issue for things that are executed on many objects or in the inner loops of some algorithms etc but its nice not to have to worry about this particular performance hazard and be able to focus your efforts elsewhere


OK, fine. that's a good, efficient way to allocate things. a nice thing when allocating things on the stack though is that freeing it is equally cheap. its just wasteful to reach for the heap for temporary objects

quote:

Escape analysis is a technique by which the Java Hotspot Server Compiler can analyze the scope of a new object's uses and decide whether to allocate it on the Java heap.

Escape analysis is supported and enabled by default in Java SE 6u23 and later.

Zlodo posted:

I disagree. the biggest cost might very well be the GC but dereferencing a pointer is significant enough compared to having the right value in a register in the first place, especially as value types allow compilers to store the fields of small structs directly into registers

of course like everything it only becomes an issue for things that are executed on many objects or in the inner loops of some algorithms etc but its nice not to have to worry about this particular performance hazard and be able to focus your efforts elsewhere


OK, fine. that's a good, efficient way to allocate things. a nice thing when allocating things on the stack though is that freeing it is equally cheap. its just wasteful to reach for the heap for temporary objects

Dessert Rose posted:

lol if you can't think of a way you'd actually use this

like obviously a list of keyvaluepairs isn't useful but i didnt feel like coming up with a real example

i sort of assumed that the use would be obvious to anyone that wasn't an idiot but i guess i am in the terrible programmer thread so here are a couple of better ones

code:

using System.Threading;
using System.Timers;

ok so now if i want a Timer what namespace does it come from? there's System.Threading.Timer and System.Timers.Timer

obviously i want a System.Timers.Timer or i wouldnt have used the namespace but the compiler will barf on it so

code:

using Timer = System.Timers.Timer;

omg now i can just write Timer in my code and it goes to the right one instead of me having to use System.Timers.Timer timer; everywhere

disambiguation is most of how it gets used but again, generics can get kind of verbose. i mean do you really want a

code:

ConcurrentDictionary<Tuple<string, int>, IEnumerable<List<Butt>>> cd = new ImNotEvenTypingThisShit();

when you could just do

code:

using ButtCollection = ConcurrentDictionary<Tuple<string, int>, IEnumerable<Task<Butt>>>;
ButtCollection cd = new ButtCollection();

maybe you dont use generics enough in your own code for it to matter but with stuff like IEnumerable<> and Task<> floating around now your code is going to look messy as gently caress without these

fritz posted:

there was a slapfight in the scicomp stack exchange clone about a year ago re: this and i think the results ended up being inconclusive w/r/t/ c vs fortran and there were problems w/ people using free compilers or pay compilers and stuff like that

Brain Candy posted:

zokie posted:

This was pretty neat but couldn't you just get your job to buy you ReSharper? Or just start exploiting that Intellisense knows about camel- and pascal-casing?

Dessert Rose posted:

yeah this totally solves the problem

also lol if you don't have a personal r# license and you write more than ten lines of c# a year

Dessert Rose posted:

yeah this totally solves the problem

also lol if you don't have a personal r# license and you write more than ten lines of c# a year

Shinku ABOOKEN posted:

what does resharper add that vs doesnt already have? legit question

i never found vs lacking in quality of life features like refactoring etc. so i never bothered with f#

qntm posted:

...
Hint: almost all popular programming languages call by value. This includes C, Java, Python and PHP. The most notable exception is Perl.

(Some programming languages allow you to call by reference if you use special syntax. This includes PHP and C#.)

Look out!

Confusingly, many call-by-value programming languages pass an object reference as their value.
...
Hint: almost all popular call-by-value programming languages use a reference to the object as their value. This includes Java and Python.

Brain Candy posted:

woaw slow down hoss with your 'measurements'. fortran is the fastest because i saw a benchmark five years ago saying that. now I believe it for all time and any of your stinky evidence is just you trying to trick me into using an inferior solution.

Shinku ABOOKEN posted:

what does resharper add that vs doesnt already have? legit question

i never found vs lacking in quality of life features like refactoring etc. so i never bothered with f#

Bloody posted:

when is vs2013 coming out? i see the RC is already up and i want to make sure to nab it before my dreamspark account goes away forever

my stepdads beer posted:

{'default': {'ENGINE': 'django.db.backends.mysql',

FamDav posted:

are you telling me that this mostly java

code:

class MyClass
{
	public int x;
}

void swap(MyClass a, MyClass b)
{
	int tmp = a.x;
	a.x = b.x;
	b.x = tmp;
}

doesn't swap the contents of a and b

Nomnom Cookie posted:

is everything still ALL CAPS

DESIGN LANGUAGE. METRO. MODERN. MINIMALIST. BUILD PROJECT

Jonny 290 posted:

word