lambda-language
just for study
reference
The toy language is written by javascript(basic now)
install
npm install implement-a-pl
syntax
ref the example
API
The following are located in the corresponding file in src
- InputStream: output lex
- TokenStream: output token
- parser: output ast
- codeGen: complier the ast to JS
- Environment: store variables
- Environment.Execute: execute ast with guarding stack
- Environment.evalute: eval ast expression with an env
run the language
bin/lambda demo
complier the language to JS
bin/code-to-js demo2 [demo2.js]
example about syntax
print_range = λ(a, b) if a <= b {
println(a);
if a + 1 <= b {
print_range(a + 1, b);
}
else
println("");
};
print_range(1, 10);
output:
1
2
3
4
5
6
7
8
9
10
***Result: false
cons = λ(a, b) λ(f) f(a, b);
car = λ(cell) cell(λ(a, b) a);
cdr = λ(cell) cell(λ(a, b) b);
NIL = λ(f) f(NIL, NIL);
x = cons(1, cons(2, cons(3, cons(4, cons(5, NIL)))));
println(car(x)); # 1
println(car(cdr(x))); # 2
println(car(cdr(cdr(x)))); # 3
println(car(cdr(cdr(cdr(x))))); # 4
println(car(cdr(cdr(cdr(cdr(x)))))); # 5
output:
1
2
3
4
5
***Result: false
code = fs-readFileSync("./demo");
println(code);
println(os-arch());