Quine
Quine is a programming puzzle. It lays out a problem which Rosetta Code users are encouraged to solve, using languages and techniques they know. Multiple approaches are not discouraged, so long as the puzzle guidelines are followed. For other Puzzles, see Category:Puzzles.
Print out a program's own source code without reading from the source file.
Ada
with Text_Io; procedure Self is Q:Character:='"'; A:String(1..132):="with text_io;procedure self is q:character:=;a:string(1..132):=;begin text_io.put_line(a(1..45)&q&a(46..65)&q&a&q&a(66..132));end;"; begin Text_Io.Put_Line(A(1..45)&Q&A(46..65)&Q&A&Q&A(66..132)); end;
Befunge
The code space is also the data space of a Befunge program. Programs can be read and modified on the fly. This quine works by reading and printing each character of the source. (This is a implicit loop, since the Befunge codespace wraps around.)
:0g,:66+`#@_1+
Forth
SOURCE TYPE
Haskell
The obvious solution, as a one-liner:
let q s = putStrLn $ s ++ show s in q "let q s = putStrLn $ s ++ show s in q "
Having the string at the end makes things a bit simpler than in generic version mentioned in the Wikipedia article.
Haskell does not keep the code in an uncompiled-equivalent form around at runtime, so the "quotation trick" has to be used.
Seed7
$ include "seed7_05.s7i"; const array string: prog is []( "$ include \"seed7_05.s7i\";", "const array string: prog is [](", "const proc: main is func", " local var integer: number is 0;", " begin", " for number range 1 to 2 do writeln(prog[number]); end for;", " for number range 1 to 11 do", " writeln(literal(prog[number]) <& \",\");", " end for;", " writeln(literal(prog[12]) <& \");\");", " for number range 3 to 12 do writeln(prog[number]); end for;", " end func;"); const proc: main is func local var integer: number is 0; begin for number range 1 to 2 do writeln(prog[number]); end for; for number range 1 to 11 do writeln(literal(prog[number]) <& ","); end for; writeln(literal(prog[12]) <& ");"); for number range 3 to 12 do writeln(prog[number]); end for; end func;
Original source: [1]