Sometimes you don't want to write out a full class description with types annotated. You don't care that there's inefficiencies in memory, that the type of the object needs to be stored in memory with its value. Sometimes you just want to smash out
Almost all uses of deferred evaluation are about cleaning up things that are dangling. Freeing memory, releasing contexts, closing files, etc. There's two kinds of 'thing' we need to consider when we want to clean up: 1) something on the stack that owns on to stuff
I think it's a good idea to write simple programs from time to time to see what you might have right or wrong with the language design. So let's try writing a program that counts the number of vowels in a string. vowels :: 'aeiou'
Right now () creates a subexpression. It is an expression in the parse tree which means something like foo () has no meaning in the language where foo is a variable. Given that foo[index] does have a meaning, and foo {a: b} also has a meaning (array indexing and object focusing)
It dawned on me looking at some old notes that I once had an idea for generic container using the sub-index syntax. Instead of Array of: Person you'd write Array[Person]. I wondered - well, can't I do that in STZ right now? and do I
Instead of writing an interpreter, what if we built the language so it compiles every layer from the very bottom to the very top. What limitations would we need to place on ourselves to make that possible? The first thing we need to consider is what the output of the
Template strings solve a lot of text based feedback problems. Instead of having string builders and concatenations and memory allocation headaches, we can instead create a composite string using a template. [self make-html: page] [self: Progam, page: Page -> String | `<html> <head> <title>
Signed and Unsigned Integers are pretty core to programming in a not-assembler level language. For STZ I'd like to represent Signed and Unsigned Integers as, internally, binary data. bits: (Binary of: 8) = 0b01010101. How many bits you have determines what kind of storage it can fit in to.
Meta-programming is an important capability to have in a language. It's not necessary if you want to build every bell and whistle in to a language at its core, but it allows you to incrementally improve a language if you know you won't have it all
Consider this innocent method: [list add: element] [List of: element, element -> list | ...code goes here...] And now ruin its day: list :: 1. element :: 2. What does this mean? We've now effectively locked the method signature to only one use case: 1 add: 2 which will fail
We twisted our arm a little bit to make stuff in a second allocator and then copy the result back in to the first allocator. It'd be better if it were allocated in the first allocator to begin with and we didn't have any temporary stuff
STZ is multithreaded. Therefore globals that aren't const are very bad. We still need a way to conveniently pass around some 'global like' information though. Let's consider the most important one - memory management. There's a school of thought that says you
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The idea that we can support different kinds of coroutines libraries in STZ makes me happy. So much so I think it's worth abandoning the Smalltalk-80 fork API and providing the libraries as-is, with some nice wrapping to clean them up. Tina provides us not only with asynchronous
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Let's approach coroutines as something we utilise rather than get in the language. Using the minicoro library and the ability to use C code directly from STZ, let's see what it'll take to utilise. Starting with the basics - let's create a
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It will come as no surprise to people who know me that using <> as a grouping mechanism for any kind of information is distasteful. It visually conflicts with less than, greater than, etc. It's already visually conflicting with select> and do>. I made all
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(Integer | 1,) (my-object | b | c) (MyType | my-object | b | c,) The | is used in a lot of places to delineate between 'the type' and 'the code' inside of list creation (type | ...elements...), methods and blocks [type | ...code...], new object {type | ...code list...}. We have also been using
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There's two ways to pass objects as parameters in a method. Either as a copy or as a reference. If we're simply using the data, we pass it as a copy. If we intend to modify it we pass it as a reference. Copying large objects
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Just for fun let's try and write a low level program using mmap to read a file and write it to stdout. requires: 'libc'. [main: arguments] [filename := arguments[0] else| panic. // Open file or die fd := (libc open: filename flags: O_RDONLY) else| panic. --- [libc
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[self my-method: arg] [:MyClass, :Integer -> ø | [ -> break | arg = 1 then: [self do-thing-one; break]; arg = 2 then: [self do-thing-two; break]; arg = 3 then: [self do-thing-three-fall-through]; arg ≤ 4 then: [self do-thing-four; break]; self do-thing-default; ] self do-other-stuff] This falls out of the current syntax nicely. You can even assign
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I know I've painted this bike shed a few times but it dawned on me that it's iterated enough that we can swing back around to some Smalltalk syntax. The original idea was to use [ signature | types | code ] and [ types | code ] to reflect the Smalltalk-80 block
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Let's try again but this time we do things the simpler way. Brick and Mortar. That's the idea of low level programming anyway. Nothing fancy. We have a few combinations we care about: socket file array block socket X X X X file X X X
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It's worth considering just how the | operator works when it hits a terminal. There are three cases we want to consider 1) processing with a block, 2) writing in to another collection, and 3) writing to a socket. In the first scenario we want to read from the
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Let's try and code something simple. A tree of nodes: Node (name: String, children: (Array of: Node)) We can likely use this right away to simulate HTML (without attributes): document: Node = {name: 'html', children: ( {name: 'head'}, {name: 'body'}) } Let's keep
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Sometimes you have a piece of data and you want to treat it differently to how it currently is. Let's take a concrete example: a filename. Not a file, but its name. It could include a path, it might not. Underneath it all, it's a bunch