Quines

.editorconfig

# http://editorconfig.org
root = true

[*]
indent_style = space
indent_size = 2
end_of_line = lf
charset = utf-8
trim_trailing_whitespace = true
insert_final_newline = true

[Makefile]
indent_style = tab

# Use 4 spaces for the Python files
[*.py]
indent_size = 4
max_line_length = 80

# The JSON files contain newlines inconsistently
[*.json]
insert_final_newline = ignore

# Minified JavaScript files shouldn't be changed
[*.md]
trim_trailing_whitespace = false

.gitignore

output/

README.md

Quines

Quines are named after the American mathematician and logician Willard Van Orman Quine (1908–2000)

References

• Wikipedia Quibe entry
• Rosetta Code Quine page
• The Quine Page by Gary P. Thompson II

cheater-quine.js

;(function quine() {
  console.log(";(" + quine.toString() + ")()")
})()

less-simple.rb

CODE = "def foo(s) \"\"; end\n\nputs \"CODE = \#{foo(CODE)}\\n\\n\#{CODE}\""

def foo(s) s.gsub('\\', '\\\\\\').gsub(/\n/, '\n').gsub(/"/, '\"').gsub(/#/, '\#').gsub(/\A|\Z/, '"'); end

puts "CODE = #{foo(CODE)}\n\n#{CODE}"

Makefile

#!/usr/bin/make --warn-undefined-variables
QUINES := $(wildcard *.py *.js *.go *.bash *.c *.rb)
OUTPUTS := $(addprefix output/,$(QUINES))

QUIET := true

.phony: all
all: $(OUTPUTS)

.phony: diff
diff: $(OUTPUTS)
	@for quine in $(QUINES); do diff -us "$$quine" "output/$$quine"; done

.phony: clean
clean:
	@rm -f $(OUTPUTS)

.phony: files
files:
	@ls -1 Makefile $(QUINES)

.phony: watch
watch:
	@while ! (make files | entr -d make diff); do sleep 0.1; done

output/.stamp:
	echo narf $@ narf
	mkdir -p $(dir $@)
	date > output/.stamp

$(OUTPUTS): output/.stamp

output/%.py: %.py
	python3 $< > $@

output/%.rb: %.rb
	ruby $< > $@

output/%.js: %.js
	node $< > $@

output/%.go: %.go
	go run $< > $@

output/%.bash: %.bash
	bash $< > $@

output/%.c: %.c
	cc $< -o output/$(basename $<)
	output/$(basename $<) > $@
	@rm -f output/$(basename $<)

quine.c

#include <stdio.h>

static char sym[] = "\n\t\\\"";

int main(void) {
	const char *code = "#include <stdio.h>%c%cstatic char sym[] = %c%cn%ct%c%c%c%c%c;%c%cint main(void) {%c%cconst char *code = %c%s%c;%c%cprintf(code, sym[0], sym[0], sym[3], sym[2], sym[2], sym[2], sym[2], sym[2], sym[3], sym[3], sym[0], sym[0], sym[0], sym[1], sym[3], code, sym[3], sym[0], sym[1], sym[0], sym[0], sym[1], sym[0], sym[0]);%c%c%creturn 0;%c}%c";
	printf(code, sym[0], sym[0], sym[3], sym[2], sym[2], sym[2], sym[2], sym[2], sym[3], sym[3], sym[0], sym[0], sym[0], sym[1], sym[3], code, sym[3], sym[0], sym[1], sym[0], sym[0], sym[1], sym[0], sym[0]);

	return 0;
}

simple-quine.go

package main

import "fmt"

const strStart = 71

func main() {
	code := `package main

import "fmt"

const strStart = 71

func main() {
	code :=
	fmt.Print(code[:strStart] + " \u0060" + code + "\u0060" + code[strStart:])
}
`
	fmt.Print(code[:strStart] + " \u0060" + code + "\u0060" + code[strStart:])
}

simple-quine.py

a = 'print("a = %r" % a)\nprint(a)'
print("a = %r" % a)
print(a)

simple.rb

code = "code = %s\n\nputs format(code, code.inspect)"

puts format(code, code.inspect)