diff options
Diffstat (limited to 'README.org')
| -rw-r--r-- | README.org | 76 |
1 files changed, 0 insertions, 76 deletions
diff --git a/README.org b/README.org deleted file mode 100644 index e223f66..0000000 --- a/README.org +++ /dev/null @@ -1,76 +0,0 @@ -#+title: Stem - -* Credits -Big thanks to Andrei Sova for contributing ~fib.stem~ in the ~examples/~ directory. -* Introduction -Stem aims to be a small implementation of something like the forth programming language, -meaning it operates on a virtual stack. There are words, quotes, and literal types in this -language; this allows for metaprogramming. - -** Quickstart -In this language, words are anything that are not literals (strings, ints, floats), and are -not the special characters [ and ]. Literals include the types above and they work just -like in other languages, and quotes are just lists of these words and literals. - -Any literal in the language by itself gets pushed onto the stack. For example, the value: -#+begin_example -"hello world" -#+end_example -gets pushed onto the stack once it is created. - -Note that words can also act like literals, but they are different in that you can bind them to funtions: -#+begin_example -helloworld [ "hello world" . ] func -#+end_example -Where . is a builtin function that pops the first value off the stack and prints it. In this example, the helloworld -word is pushed onto the stack, then the quote ~[ "hello world" . ]~, which is just an array of these two values. Then, -the ~func~ builtin is called, which takes these two values off of the stack. As a result, whenever ~helloworld~ is used -in the future, it is expanded into whatever is in the quote. - -a useful way to know what's on the stack: -#+begin_example -? -#+end_example -is a builtin function that prints everything on the stack, where the very last thing printed is the top of the stack. - -*** Quoting and Escaping -If you want to push a word to the stack after it has been bound, you must escape it: -#+begin_example -\helloworld -#+end_example - -quotes are somewhat related to escaping. They allow the language to talk about itself, along with the ~eval~ keyword. -To get an idea of what you can do with it, consider the following example: -#+begin_example -[ hello [ "hello" . ] func ] eval -#+end_example -this statement is essentially the same statement as the above, but you can represent the entire code in a quote -before evaluation. This allows for many possibilities. For example, you may try writing a program that automatically -names functions and automatically changes what those functions do. - -*** Loops -Looping in this language is done via recursion. Because the language is stack-based, recursion is not more memory efficient -than looping if using tail recursion. For example, the REPL for this language is implemented like so: -#+begin_example -loop [ "> " . read strquote eval loop ] func loop -#+end_example -Where read takes in a string and prints it before reading a value, strquote turns a string into a quote, and loop is the function that calls -itself. - -*** Curry, Compose, Qstack, Quote -These functions are important for manipulating quotes. For example: -#+begin_example -[ a b ] 6 5 quote curry compose -#+end_example -first turns 5 into ~[ 5 ]~, then curry adds 6 to the end of the quote. Compose takes two quotes and adjoins them together. Qstack -simply turns everything on the stack into a quote, then puts it on the stack. For example: -#+begin_example -1 2 3 4 5 6 7 qstack -#+end_example -Returns the quote ~[ 1 2 3 4 5 6 7 ]~. -* CLib -This language has a foreign language interface (FLI). The FLI functions via including ~parser.h~ and creating the functions -~add_funcs~ and ~add_objs~. Each custom object needs to have its own free, print, and copy functions. For some implementation examples, -see the ~builtins.c~ file. Later on there will be more documentation. -* Install -~make~ and ~sudo make install~. |