Hello, World!
(format t "Hello, World!~%")main.lisp
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main.lisp · output appears here
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Lisp 2.4.4Readymain.lispLn 1, Col 1Spaces: 4UTF-8
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main.lisp · output appears here
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Lisp is a family of programming languages originating from a design by John McCarthy in 1958, making it one of the oldest high-level languages still in use. It is famous for its fully parenthesized prefix notation (S-expressions), treating code as data, and powerful macro system. Lisp pioneered ideas such as garbage collection, the read-eval-print loop, and first-class functions, and it strongly influenced functional programming.
On CompileBytes, Lisp programs run on SBCL (Steel Bank Common Lisp), reported as version 2.1.2. Common Lisp is a large, multi-paradigm standardized dialect supporting functional, imperative, and object-oriented styles via CLOS. SBCL is a high-performance, open-source implementation that compiles to native code. Lisp is used in artificial intelligence research, symbolic computation, rapid prototyping, and teaching the fundamentals of metaprogramming.
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(format t "Hello, World!~%")(defun square (n)
(* n n))
(format t "Square of 5 is ~a~%" (square 5))(defun factorial (n)
(if (<= n 1)
1
(* n (factorial (- n 1)))))
(format t "~a~%" (factorial 6))(dolist (x '(1 2 3 4 5))
(format t "Value: ~a~%" x))(let ((nums '(1 2 3 4 5)))
(format t "Squares: ~a~%" (mapcar (lambda (x) (* x x)) nums))
(format t "Sum: ~a~%" (reduce #'+ nums)))(dotimes (i 5)
(format t "i = ~a~%" i))(let ((x 7))
(cond ((evenp x) (format t "~a is even~%" x))
(t (format t "~a is odd~%" x))))(let ((squares (loop for i from 1 to 5 collect (* i i))))
(format t "~a~%" squares))(let ((ages '((ada . 36) (tom . 42))))
(format t "Ada is ~a~%" (cdr (assoc 'ada ages))))The editor uses Monaco, the engine behind VS Code, with language-aware editing tools and familiar keyboard controls.
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Lisp is one of 46 single-file compiler scratchpads. Each run submits only main.lisp; local sibling-file imports are not enabled.
Linked-project languages (23): Node.js, TypeScript, Deno, Python, C, Go, Dart, Swift, Rust, Ruby, PHP, Java, Kotlin, C++, C#, Nim, Crystal, Haxe, Zig, Scala, D, Bun, Objective-C.
Single-file scratchpads (46): Matplotlib, NumPy, pandas, Haskell, Clojure, Perl, Lua, Tcl, jq, Raku, Elixir, Bash, Zsh, Nushell, R, Assembly (NASM), Julia, Octave, Groovy, PowerShell, Visual Basic .NET, Odin, Pascal, Lisp, Erlang, CoffeeScript, COBOL, BASIC, V, Racket, OCaml, Prolog, AWK, Emacs Lisp, Emojicode, Forth, F#, Fortran, Assembly (NASM64), Solidity, Mojo, Ada, WASM (WAT), Gleam, Shell Script (sh), Scheme.
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