| /* | |
| Compile with one of the following: | |
| zig cc -v -s -Os -target aarch64-linux-musl -nostdlib -flto -static shell.c -o csh | |
| zig cc -v -s -Os -target aarch64-linux-gnu -nostdlib -flto -static shell.c -o csh | |
| CLANG: | |
| clang -v -s -Oz -ffreestanding -nostdlib -fno-stack-protector -Wl,--entry=_start -Wl,--gc-sections -Wl,-z,now -flto -static -o csh shell.c | |
| musl-clang -v -s -Os -nostdlib -nostartfiles -fno-stack-protector -Wl,--entry=_start -Wl,--gc-sections -Wl,-z,now -flto -nostdinc -static -o csh shell.c | |
| GCC (some things DO NOT WORK like `pwd`): |
| let discard _a b = b | |
| let rec pp lvl = function | |
| | `Lam f -> "(λ" ^ pp (lvl + 1) (f (`Go lvl)) ^ ")" | |
| | `Pi (a, f) -> "(Π" ^ pp lvl a ^ "." ^ pp (lvl + 1) (f (`Go lvl)) ^ ")" | |
| | `Appl (m, n) -> "(" ^ pp lvl m ^ " " ^ pp lvl n ^ ")" | |
| | `Ann (m, a) -> "(" ^ pp lvl m ^ " : " ^ pp lvl a ^ ")" | |
| | `Go x -> string_of_int x | |
| | `Star -> "*" | |
| | `Box -> "☐" |
| module C : sig | |
| type t | |
| val empty : t | |
| val one : char -> t | |
| val union : t -> t -> t | |
| val inter : t -> t -> t | |
| val top : t | |
| val mem : char -> t -> bool | |
| val make : (char -> bool) -> t | |
| val equal : t -> t -> bool |
| type term = | |
| | Lam of (term -> term) | |
| | Pi of term * (term -> term) | |
| | Appl of term * term | |
| | Ann of term * term | |
| | FreeVar of int | |
| | Star | |
| | Box | |
| let unfurl lvl f = f (FreeVar lvl) |
On September 28, 2021, I asked on Twitter:
PL Twitter:
you get to recommend one published PL paper for an undergrad to read with oversight by someone experienced. the paper should be interesting, approachable, and (mostly) self-contained.
what paper do you recommend?
This project is a tiny compiler for a very simple language consisting of boolean expression.
The language has two constants: 1 for true and 0 for false, and 4 logic gates:
! (not), & (and), | (or), and ^ (xor).
It can also use parentheses to manage priorities.
Here is its grammar in BNF format:
expr ::= "0" | "1"
| // Tails has grown a bit and moved out into its own repository: https://github.com/snej/tails/ | |
| // Please visit it there! | |
| // | |
| // If you want to see the tiny original version from May Forth 2021, it's still here; | |
| // click the "Revisions" button above, or go to: | |
| // https://gist.github.com/snej/9ba59d90689843b22dc5be2730ef0d49/2d55f844b7622aa117b9275bbc9d189613f7ff7f |
(draft; work in progress)
See also:
It's now here, in The Programmer's Compendium. The content is the same as before, but being part of the compendium means that it's actively maintained.
| #!/bin/bash | |
| usage="Usage: $(basename "$0") <name>" | |
| if [ $# -ne 1 ]; then | |
| echo $usage | |
| exit 0 | |
| fi | |
| proj=$1 |
