xeruf / mlisp-interpreter

Interpreter for Mini Lisp written in Kotlin

Mini LISP

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Expression based

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(+ 4 5) # evaluates to -> 9

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Predefined functions

​ +, =, print, list, first, rest, append ​

(+ 1 2) # -> 9
(= 1 1) # -> true
(= 1 2) # -> () which is an empty list and equivalent to false

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(print 1) # outputs  1

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(list 1 2 3) # -> (1 2 3)

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(first (1 2 3)) # -> 1
(rest (1 2 3)) # -> (2 3)
(append (1 2 3) 4) # -> (1 2 3 4)

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define variables

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(define a 1)  # a is bound to 1
(define b (+ 3 4)) # b is bound to 7
```​
## define functions
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```lisp
(define twice lambda (a) (+ a a))  # twice is a function that calculates a + a
(define sum lambda (a b) (+ a b)) # b is bound to 7

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Conditionals

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(define a 5)
(if (= a 7) (twice a) (twice 2)) # evaluates to 4 (twice 2)
(if (= a 5) (twice a) (twice 2)) # evaluates to 10 (twice a)