language-design

So I've been reading these two articles and this answer Cannot convert []string to []interface {} says that the memory layout needs to be changed. http://jordanorelli.com/post/32665860244/how-to-use-interfaces-in-go says that understanding the underlying memory makes answering this question easy, and http://research.swtch.com/interfaces , explains what is going on under the hood. But for the life of me I can't think of a reason, in terms of the implementation of interfaces as to why []T cannot be cast to []interface. So Why? VonC The article " InterfaceSlice " try to detail: A variable with

I've read everywhere that PHP does not support multithreading but there are workarounds. But why does PHP not support multithreading? For a server-side scripting language, that seems like a glaring omission. Edit several years later: you can use pthreads for PHP multithreading, but do you really want to? I'm not sure if pthreads is available on many hosting environments. And frankly I am not in a rush to find out. One of PHP's biggest strengths for many applications is its isolation: one process, one request. Multi-processing is usually done by queuing a job during a request and executing it

Is there a java compiler flag that allows me to use goto as a valid construct? If not, are there any third-party java compilers that supports goto ? If not, are there any other languages that support goto while at the same time can easily call methods written in Java? The reason is I'm making a language that is implemented in Java. Gotos are an important part of my language; I want to be able to compile it to native or JVM bytecode, although it has to be able to easily use Java libraries (ie. C supports goto , but to use it I'd have to rewrite the libraries in C). I want to generate C or Java,

I am reading Scala and I am wondering ... Why val capacity : Int instead of val Int capacity. Any reason why this choice was made. If not, it does not seem to me like a good choice to move away from the Java way of declaring it. Would have made the transition from Java to Scala easier (not by much, but little bit) Because the majority of the time you can leave off the Int part. Scala has a much neater system of type inference than Java does. I think I read a statement by Martin Odersky himself somewhere saying that this decision was also made in order to improve readability. This is certainly

I have a method which takes a generator plus some additional parameters and yields a new generator: function merge(\Generator $carry, array $additional) { foreach ( $carry as $item ) { yield $item; } foreach ( $additional as $item ) { yield $item; } } The usual use case for this function is similar to this: function source() { for ( $i = 0; $i < 3; $i++ ) { yield $i; } } foreach ( merge(source(), [4, 5]) as $item ) { var_dump($item); } But the problem is that sometimes I need to pass empty source to the merge method. Ideally I would like to be able to do something like this: merge(\Generator:

Why was C++ designed such that the correct way to declare two int *s on the same line is int *x, *y; not int* x,y; I know some people think you should avoid either form and declare every variable on its own line, but I'm interested in why this language decision was made. To keep compatibility with C code, because that's how C works. Bjarne makes a good point here : The choice between int* p; and int *p; is not about right and wrong, but about style and emphasis. C emphasized expressions; declarations were often considered little more than a necessary evil. C++, on the other hand, has a heavy