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{{task|Iteration}} [[Category:Simple]]
;Task: Print out '''SPAM''' followed by a ''newline'' in an infinite loop.
;Related tasks:
- [[Loop over multiple arrays simultaneously]]
- [[Loops/Break]]
- [[Loops/Continue]]
- [[Loops/Do-while]]
- [[Loops/Downward for]]
- [[Loops/For]]
- [[Loops/For with a specified step]]
- [[Loops/Foreach]]
- [[Loops/Increment loop index within loop body]]
- [[Loops/Infinite]]
- [[Loops/N plus one half]]
- [[Loops/Nested]]
- [[Loops/While]]
- [[Loops/with multiple ranges]]
- [[Loops/Wrong ranges]]
360 Assembly
This for sure will result in a severe WTO buffer shortage.
INFINITE CSECT , this PGM control section
INFINITE AMODE 31 addressing mode 31 bit
INFINITE RMODE ANY loader can load either 24 or 31
BAKR 14,0 stack caller's register contents
LR 12,15 establish base
LA 13,0 no savearea
USING INFINITE,12 base to assembler
LA 10,1 1 in reg 10
LA 11,2 2 in reg 11
LOOP EQU *
CR 10,11 1==2?
BE RETURN Yes, exit.
WTO 'SPAM',ROUTCDE=11 print SPAM to syslog
B LOOP No, check again.
RETURN PR , return to caller
END INFINITE
4DOS Batch
@echo off
do forever
echo SPAM
enddo
6502 Assembly
Specific OS/hardware routines for printing are left unimplemented.
InfiniteLoop LDX #0
PrintLoop: LDA MSG,x
JSR PrintAccumulator ;routine not implemented
INX
CPX #5
BNE PrintLoop
BEQ InfiniteLoop
MSG .byte "SPAM", $0A
6800 Assembly
===============================================
; ; Infinite SPAM loop for the Motorola 6800 ; ; by barrym 2013-04-10 ; ;-----------------------------------------------------; ; Prints the message "SPAM" repeatedly to an ascii ; ; terminal (console) connected to a 1970s vintage ; ; SWTPC 6800 system, which is the target device for ; ; this assembly. ; ; Many thanks to: ; ; swtpc.com for hosting Michael Holley's documents! ; ; sbprojects.com for a very nice assembler! ; ; swtpcemu.com for a very capable emulator! ; ; reg x is the string pointer ; ; reg a holds the ascii char to be output ; ;-----------------------------------------------------; outeee = $e1d1 ;ROM: console putchar routine .or $0f00 ;-----------------------------------------------------; main ldx #string ;Point to the string bra puts ; and print it outs jsr outeee ;Emit a as ascii inx ;Advance the string pointer puts ldaa ,x ;Load a string character bne outs ;Print it if non-null bra main ;else restart ;
===============================================
; string .as "SPAM",#13,#10,#0 .en
## 8th
One way:
```forth
: inf "SPAM\n" . recurse ;
Another way:
: inf repeat "SPAM\n" . again ;
ACL2
(defun spam ()
(declare (xargs :mode :program))
(if nil
nil
(prog2$ (cw "SPAM~%")
(spam))))
ActionScript
while (true) {
trace("SPAM");
}
Ada
loop
Put_Line("SPAM");
end loop;
Agena
Tested with Agena 2.9.5 Win32
do
print( "SPAM" )
od
Aime
while (1) {
o_text("SPAM\n");
}
ALGOL 60
{{trans|ALGOL W}}
'''Based on the 1962 Revised Repport on ALGOL''': '''begin''' '''integer''' i; '''for''' i:=1 '''step''' 0 '''until''' 2 '''do''' outtext("spam") '''end''' {{works with|ALGOL 60|OS/360}}
'BEGIN' 'COMMENT' Loops/Infinite - Algol60 - 23/06/2018;
'INTEGER' I;
'FOR' I := 1 'STEP' 0 'UNTIL' 2 'DO'
OUTSTRING(1,'('SPAM')')
'END'
ALGOL 68
DO
printf($"SPAM"l$)
OD
Or the classic "dynamic halt":
loop x:
printf($"SPAM"l$);
loop x
ALGOL W
begin
for i := 1 step 0 until 2 do write( "SPAM" )
end.
AmigaE
PROC main()
LOOP
WriteF('SPAM')
ENDLOOP
ENDPROC
AppleScript
repeat
log "SPAM"
end repeat
ARM Assembly
main:
loop: ldr r0, =message bl printf b loop
message: .asciz "SPAM\n"
## ArnoldC
```ArnoldC
IT'S SHOWTIME
STICK AROUND @NO PROBLEMO
TALK TO THE HAND "SPAM"
CHILL
YOU HAVE BEEN TERMINATED
Arturo
loop true {
print "SPAM"
}
AutoHotkey
Loop
MsgBox SPAM `n
AWK
BEGIN {
while(1) {
print "SPAM"
}
}
Axe
Warning: running this program will cause you to need to reset your calculator, thereby losing any user data stored in RAM.
While 1
Disp "SPAM",i
End
BASIC
{{works with|QuickBasic|4.5}} Old-fashioned syntax:
while 1
print "SPAM"
wend
Standard BASIC:
do
print "SPAM"
loop
Also
for i = 1 to 10 step 0
print "SPAM"
next i
{{works with|Applesoft BASIC}} {{works with|Commodore BASIC}} {{works with|ZX Spectrum Basic}}
10 PRINT "SPAM"
20 GOTO 10
Rather than a GOTO, instead we can use a FOR statement:
10 FOR I = 1 TO 10 STEP 0: REM A zero step makes the loop infinite
20 PRINT "SPAM"
30 NEXT I
=
Applesoft BASIC
=
FOR I = 0 TO 1 STEP 0 : PRINT "SPAM" : NEXT
==={{header|IS-BASIC}}===
## Batch File
Using <code>goto</code>:
```dos
@echo off
:loop
echo SPAM
goto loop
Another variant which uses Windows NT's for
statement:
{{works with|Windows NT|4 or later}}
for /l %%x in (1,0,2) do @echo SPAM
This essentially is a counted loop which starts at 1
, increments by 0
and stops when the counter reaches 2
.
BBC BASIC
REPEAT
PRINT "SPAM"
UNTIL FALSE
bc
while (1) "SPAM
"
beeswax
_>`SPA`p
bN`M`<
Befunge
Because the 2-D code space is toroidal, all loops are infinite unless explicitly stopped with '''@'''.
55+"MAPS",,,,,
blz
while true
print("SPAM")
end
=={{header|Brainfuck}}== Optimized for code size:
++++++++++[->++++++>++++++++>+<<<]>+++++>
[+++.---.<.>---.+++>.<]
Optimized for execution speed:
10++++++++++
[-> 8++++++++ > 8++++++++ > 6++++++ > 8++++++++ > 1+ <<<<<]>
83+++ > 80 > 65+++++ > 77--- <<<
[.>.>.>.>.<<<<]
Bracmat
whl'out$SPAM
Brat
loop { p "SPAM" }
C
while(1) puts("SPAM");
or
for(;;) puts("SPAM");
or
do { puts("SPAM"); } while(1);
or
while(puts("SPAM"));
or
spam: puts("SPAM");
goto spam;
ChucK
## C++
{{trans|C}}
```cpp
while (true)
std::cout << "SPAM\n";
or
for (;;)
std::cout << "SPAM\n";
or
do
std::cout << "SPAM\n";
while (true);
C#
while (true)
{
Console.WriteLine("SPAM");
}
Chapel
while true do writeln("SPAM");
ColdFusion
This will result in a JRun Servlet Error and heap dump.
With tags:
<cfloop condition = "true NEQ false">
SPAM
</cfloop>
With script:
while( true != false )
{
writeOutput( "SPAM" );
}
</cfscript>
Clojure
(loop [] (println "SPAM") (recur))
COBOL
IDENTIFICATION DIVISION.
PROGRAM-ID. Spam.
PROCEDURE DIVISION.
PERFORM UNTIL 1 <> 1
DISPLAY "SPAM"
END-PERFORM
GOBACK
.
[[OpenCOBOL]] supports a FOREVER
clause for PERFORM
which will have the same effect.
CoffeeScript
loop
console.log 'SPAM'
Comal
LOOP
PRINT "SPAM"
ENDLOOP
Common Lisp
(loop (write-line "SPAM"))
D
Some common ways to create an infinite printing loop:
import std.stdio;
void main() {
while (true)
writeln("SPAM");
}
import std.stdio;
void main() {
do
writeln("SPAM");
while (true);
}
import std.stdio;
void main() {
for ( ; ; )
writeln("SPAM");
}
import std.stdio;
void main() {
LOOP:
writeln("SPAM");
goto LOOP;
}
Dart
## dc
```dc
[[SPAM
]P dx]dx
This loop is a tail-recursive function. The program pushes the function on the stack, the outer ''dx'' makes the first call, and the inner ''dx'' makes each recursive call.
DCL
$ loop:
$ write sys$output "SPAM"
$ goto loop
=={{header|Déjà Vu}}==
while true:
!print "SPAM"
Infinite recursion thanks to tail calls:
labda:
!print "SPAM"
recurse
call
Delphi
while True do Writeln('SPAM');
DWScript
while True do
PrintLn('SPAM');
Dyalect
while true {
print("SPAM")
}
E
while (true) {
println("SPAM")
}
def f() {
println("SPAM")
f <- ()
}
f <- ()
The difference between these is that in the second, other activities can be interleaved with the loop; in the first, no other processing will occur in this vat.
EDSAC order code
The EDSAC instruction set does not include an unconditional jump: it is necessary to synthesize it by using either an E
"branch on accumulator sign bit clear" or F
"branch on accumulator sign bit set" order, in circumstances where the condition is guaranteed to be met. For this specific task, guaranteeing it is trivial: printing characters does not change the contents of the accumulator at all. The solution presented here, however, is more general. We use a T
"transfer and clear" order to store the accumulator's contents in storage address θ+17, then jump back to the beginning of the loop and reload the accumulator with an A
"add" order. Note that the storage address used as a temporary variable should be set to zero on entry to the loop.
[ Infinite loop
### =======
A program for the EDSAC
Works with Initial Orders 2 ]
T56K
GK
O10@ [ letter shift ]
[ 1 ] A17@ [ a += C(17@) ]
O11@
O12@
O13@
O14@
O15@
O16@
T17@ [ C(17@) = a; a = 0 ]
E1@ [ if a >= 0 goto 1@ ]
[ 10 ] *F
[ 11 ] SF
[ 12 ] PF
[ 13 ] AF
[ 14 ] MF
[ 15 ] @F [ carriage return ]
[ 16 ] &F [ line feed ]
[ 17 ] PF
EZPF
Ela
Direct Approach
open monad io
loop () = do
putStrLn "SPAM"
loop ()
loop () ::: IO
===Non-strict version===
open monad io
xs = "SPAM"::xs
takeit 0 _ = do return ()
takeit num (x::xs) = do
putStrLn x
takeit (num - 1) xs
_ = takeit 10 xs ::: IO
Elena
ELENA 4.x:
public program()
{
while (true)
{
console.writeLine:"spam"
}
}
Elixir
defmodule Loops do
def infinite do
IO.puts "SPAM"
infinite
end
end
Loops.infinite
or
Stream.cycle(["SPAM"]) |> Enum.each(&IO.puts &1)
Erlang
-module (main).
-export ([main/0]).
main() ->
io:fwrite( "SPAM~n" ),
main().
Emacs Lisp
This is run in an external file.
#!/usr/bin/env emacs --script
(while (princ "SPAM\n"))
ERRE
LOOP
PRINT("SPAM")
END LOOP
You can use also WHILE TRUE..END WHILE or REPEAT...UNTIL FALSE loops.
Euphoria
while 1 do
puts(1, "SPAM\n")
end while
=={{header|F Sharp|F#}}==
// Imperative Solution
while true do
printfn "SPAM"
// Functional solution
let rec forever () : unit =
printfn "SPAM"
forever ()
Factor
Tail recursion:
: spam ( -- ) "SPAM" print spam ;
Looping combinators:
[ "SPAM" print t ] loop
USE: combinators.extras
[ "SPAM" print ] forever
FALSE
[1]["SPAM
"]#
Fantom
class Main
{
public static Void main ()
{
while (true)
{
echo ("SPAM")
}
}
}
Fish
a"MAPS"ooooo
Forth
: email begin ." SPAM" cr again ;
Fortran
FORTRAN 77
10 WRITE(*,*) 'SPAM'
GO TO 10
END
Fortran 90
program spam
implicit none
do
write(*,*) 'SPAM'
end do
end program spam
Fortress
component loops_infinite
export Executable
run() = while true do
println("SPAM")
end
end
FreeBASIC
' FB 1.05.0
Do
Print "SPAM"
Loop
Frink
while true
println["SPAM"]
FutureBasic
Loop de loop -- whose great idea was this?
include "ConsoleWindow"
while 1
print "Spam"
wend
Gambas
'''[https://gambas-playground.proko.eu/?gist=e63dcdc939f8a7dcfd3194d884f8d4a5 Click this link to run this code]'''
Public Sub Main()
Do
Print "SPAM"
Loop
End
GAP
while true do
Print("SPAM\n");
od;
GB BASIC
10 print "SPAM"
20 goto10
GML
while(1)
show_message("SPAM")
Go
package main
import "fmt"
func main() {
for {
fmt.Printf("SPAM\n")
}
}
Groovy
while (true) {
println 'SPAM'
}
Halon
forever {
echo "SPAM";
}
or (due to optimizations, these are equally fast)
while (true) {
echo "SPAM";
}
Haskell
forever (putStrLn "SPAM")
or
import Control.Monad.Fix (fix)
fix (putStrLn "SPAM" >>)
hexiscript
while true; println "SPAM"; endwhile
HicEst
DO i = 1, 1E20 ! for i with 16 or more digits: i == i + 1 == loop infinite
WRITE() "SPAM"
ENDDO
HolyC
while(1) Print("SPAM\n");
=={{header|Icon}} and {{header|Unicon}}== There are several ways to write infinite loops in Icon. The most straightforward would be with repeat.
procedure main()
repeat write("SPAM")
end
Alternately one could use one of these:
until &fail do write("SPAM") # always fails, needs succeed to break
...
while write("SPAM") # always succeeds, needs failure to break
...
every write(|"SPAM") # generator always succeeds, needs failure to break
...
while write(|"SPAM") # this is a common mistake that results in an endless loop
...
while write(1 to 5) # a clearer version of the same mistake that generates endless 1's
IDL
while 1 do print,'SPAM'
Intercal
Assuming Turing Text I/O with 8-bit ASCII-compatible character set, using COME FROM:
NOTE THIS IS INTERCAL
PLEASE ,1 <- #5
DO ,1 SUB #1 <- #54
DO ,1 SUB #2 <- #192
DO ,1 SUB #3 <- #136
PLEASE ,1 SUB #4 <- #208
DO ,1 SUB #5 <- #98
DO COME FROM (1)
DO READ OUT ,1
(2) DO ,1 SUB #1 <- #134
(1) PLEASE ABSTAIN FROM (2)
Io
loop("SPAM" println)
J
(-[smoutput bind 'SPAM')^:_(1)
Alternatively,
smoutput bind 'SPAM'^:1e99 ''
This second implementation relies on numeric inaccuracies in IEEE floating point notation. For example, 1+1e98 is exactly equal to 1e98. That said, 1e98 iterations would still be significantly longer than the practical life of any machine anyone would care to dedicate to this task.
Java
while (true) {
System.out.println("SPAM");
}
for (;;) {
System.out.println("SPAM");
}
JavaScript
for (;;) console.log("SPAM");
while (true) console.log("SPAM");
Joy
DEFINE loop == [true []] dip while.
["SPAM\n" putchars] loop.
jq
recurse("SPAM")
{{Out}} "SPAM" "SPAM" ...
To suppress the quotation marks, invoke jq with the -r option.
Jsish
for (;;) puts('SPAM');
Julia
while true
println("SPAM")
end
{{out}}
SPAM
SPAM
SPAM
SPAM
SPAM
SPAM
SPAM
and so on until ^C
K
while[1; `0:"SPAM\n"]
Kotlin
// version 1.0.6
fun main(args: Array<String>) {
while (true) println("SPAM")
}
LabVIEW
{{VI solution|LabVIEW_Loops_Infinite.png}}
Lang5
do "SPAM\n" . loop
Lasso
// not wise to run this!
while(1 > 0) => {^
'SPAM\r'
^}
Liberty BASIC
while 1
print "SPAM"
wend
end
Lily
while 1: print("SPAM")
Lingo
repeat while TRUE
put "SPAM"
end repeat
Lisaac
{ "SPAM\n".print; }.endless_loop;
```
## LiveCode
```LiveCode
repeat forever
put "SPAM" & return
end repeat
```
## Logo
```logo
forever [print "SPAM]
```
## LOLCODE
```lolcode
HAI
CAN HAS STDIO?
IM IN YR LOOP
VISIBLE "SPAM"
IM OUTTA YR LOOP
KTHXBYE
```
## Lua
```lua
while true do
print("SPAM")
end
--Another solution
repeat
print("SPAM")
until false
```
## M2000 Interpreter
All loops can stop using Esc or Ctrl+C or Break (the last two open dialog box to stop or continue). Using Escape Off we make Esc not work for breaking execution.
If Esc works then Ctrl + Y (and other letters except C, A, Z, X, N, M. F, L), open Control form, which we can do: Next Step, Slow Flow, Stop, and we can show code,current stack, variables, or execute immediate statements. This works only in console, not in M2000 forms.
```M2000 Interpreter
Module CheckIt {
Print "SPAM"
loop
}
Checkit
```
Using a Repeat (or Do) - Always block
```M2000 Interpreter
Module CheckIt {
Repeat {
Print "SPAM"
} Always
}
Checkit
```
Printing text rendering using Report.
```M2000 Interpreter
Module CheckIt {
\\ stop in every 2/3 of cosole lines
\\ press spacebar or mouse button to continue
Report Format$("Spam\n")
Loop
}
Checkit
\\ using multiline string, replace report from module above
Report {SPAM
}
```
## M4
```M4
define(`spam',`SPAM
spam')
spam
```
## Make
```make
spam:
@echo SPAM
$(MAKE)
```
## Maple
```Maple
> do print(SPAM) end;
```
=={{header|Mathematica}} / {{header|Wolfram Language}}==
```mathematica
While[True,
Print@"SPAM";
]
```
=={{header|MATLAB}} / {{header|Octave}}==
```Matlab
while true
fprintf('SPAM\n')
end
```
## Maxima
```maxima
do(disp("SPAM"));
```
## MAXScript
```maxscript
while true do print "SPAM\n"
```
## Metafont
```metafont
forever: message "SPAM"; endfor end
```
## Microsoft Small Basic
With While
.
```microsoftsmallbasic
While "True"
TextWindow.WriteLine("SPAM")
EndWhile
```
With Goto
.
```microsoftsmallbasic
loopStart:
TextWindow.WriteLine("SPAM")
Goto loopStart
```
## min
{{works with|min|0.19.3}}
```min
(true) ("SPAM" puts!) while
```
=={{header|MK-61/52}}==
1 2 3 4 С/П БП 00
```
''Note'': because this device has no text output instead of "SPAM" was used the number (1234).
=={{header|Modula-2}}==
```modula2
LOOP
InOut.WriteString ("SPAM");
InOut.WriteLn
END;
```
=={{header|Modula-3}}==
```modula3
LOOP
IO.Put("SPAM\n");
END;
```
## Monte
```Monte
while (true):
traceln("SPAM")
```
## MOO
```moo
while (1)
player:tell("SPAM");
endwhile
```
## MUMPS
```MUMPS
FOR WRITE "SPAM",!
```
## MontiLang
```MontiLang
WHILE TRUE
|SPAM| PRINT .
ENDWHILE
```
Note that TRUE
is simply a variable equal to 1. WHILE 1
, any number larger than 0 or any string with a length more than 0 would also work
## Nemerle
```Nemerle
while (true) WriteLine("SPAM");
```
Or, using recursion:
```Nemerle
def loop() : void
{
WriteLine("SPAM");
loop();
}
```
## NetRexx
```NetRexx
/* NetRexx */
options replace format comments java crossref savelog symbols nobinary
say
say 'Loops/Infinite'
loop label spam forever
say 'SPAM'
end spam
```
## NewLISP
```NewLISP
(while (println "SPAM"))
```
## Nim
```nim
while true:
echo "SPAM"
```
=={{header|NS-HUBASIC}}==
Using FOR
:
10 FOR I=0 TO 1 STEP 0
20 PRINT "SPAM"
30 NEXT
```
Using GOTO
:
10 PRINT "SPAM"
20 GOTO 10
```
Using RUN
:
10 PRINT "SPAM"
20 RUN
```
=={{header|Oberon-2}}==
```oberon2
MODULE InfiniteLoop;
IMPORT
Out;
BEGIN
LOOP
Out.String("SPAM");Out.Ln
END
END InfiniteLoop.
```
## Objeck
```objeck
while(true) {
"SPAM"->PrintLine();
};
```
## OCaml
```ocaml
while true do
print_endline "SPAM"
done
```
or
```ocaml
let rec inf_loop() =
print_endline "SPAM";
inf_loop()
in
inf_loop()
```
Seen like this it looks like the "too much functional" danger when a "while" loop looks far simpler, but the functional loop may be useful to provide data to the next loop without using mutable variable.
## Occam
```occam
#USE "course.lib"
PROC main (CHAN BYTE screen!)
WHILE TRUE
out.string("SPAM*c*n", 0, screen)
:
```
## Octave
```octave
while(1)
disp("SPAM")
endwhile
```
## Oforth
```Oforth
begin "SPAM" . again
```
## Ol
```scheme
(let loop ()
(display "SPAM")
(loop))
```
## OPL
```opl
PROC main:
LOCAL loop%
loop%=1
while loop%=1
PRINT "SPAM"
ENDWH
ENDP
```
## Oz
```oz
for do
{Show 'SPAM'}
end
```
## PARI/GP
```parigp
while(1,
print("SPAM")
);
```
For a shorter version, note that print
returns gnil
which is evaluated as false
.
A 'cheating' solution might use print(SPAM)
on the hope that the variable SPAM is uninitialized and hence prints as the monomial in itself.
But with the '
operator that evaluation can be forced, regardless of the current value (if any) of that variable:
```parigp
until(print('SPAM),)
```
## Pascal
```pascal
while true do
writeln('SPAM');
```
Alternatively:
```pascal
repeat
writeln('SPAM')
until false;
```
## Perl
```perl
while(1){
print "SPAM\n";
}
```
or equivalently
```perl
print "SPAM\n" while 1;
```
## Perl 6
{{works with|Rakudo Star|2010.08}}
```perl6
loop {
say 'SPAM';
}
```
In addition, there are various ways of writing lazy, infinite lists in Perl 6:
```perl6
print "SPAM\n" xx *; # repetition operator
print "SPAM\n", ~* ... *; # sequence operator
map {say "SPAM"}, ^Inf; # upto operator
```
## Phix
```Phix
while 1 do
puts(1,"SPAM\n")
end while
```
## PHP
```php
while(1)
echo "SPAM\n";
```
## PicoLisp
```PicoLisp
(loop (prinl "SPAM"))
```
## Pike
```pike
int main(){
while(1) write("SPAM\n");
}
```
## PILOT
```pilot
*TypeSpam
type:SPAM
jump:*TypeSpam
```
## PL/I
```PL/I
do forever;
put list ('SPAM'); put skip;
end;
```
## plainTeX
Compile in console mode, with, e.g. "pdftex ".
```tex
\newlinechar`\^^J
\def\spam{\message{SPAM^^J}\spam}%
\spam
```
## Pop11
```pop11
while true do
printf('SPAM', '%p\n');
endwhile;
```
## PostScript
simple infinite loop:
```postscript
{}loop
```
A bit more complex infinite loop:
```postscript
/go {
/spam
{ (SPAM\n) print flush }
bind def % bind and define spam
{ spam } % procedure that will be executed by loop and will call spam to print
loop % the loop
}
%start spamming!
go
```
## PowerShell
```powershell
for () {
"SPAM"
}
```
## Prolog
```prolog
repeat, write('SPAM'), nl, fail.
```
## Pure Data
Screenshot: https://i.imgur.com/IrwaafZ.png
```Pure Data
#N canvas 426 88 450 300 10;
#X obj 17 75 print;
#X msg 17 55 SPAM;
#X obj 17 35 metro 1;
#X msg 17 15 1;
#X connect 1 0 0 0;
#X connect 2 0 1 0;
#X connect 3 0 2 0;
```
Notes: the loop is started by clicking the |1(, a [loadbang] could additionally be used. An [until] object, sent a bang, will loop forever, but will hang Pure Data, whereas a high-speed metro will function perfectly.
## PureBasic
### Repeat/Forever
```PureBasic
Repeat
PrintN("SPAM")
ForEver
```
### Goto
```PureBasic
PrintIt:
PrintN("SPAM")
Goto PrintIt
```
## Python
In Python 2:
```python
while 1:
print "SPAM"
```
In python 3:
```python
while 1:
print("SPAM")
```
Note: one can also use: "True" or any other non-false value.
In Python the following values are false: 0, "" (empty string), (,) and {} and [] (empty tuples, dictionaries or lists), ''None'' (the special object), and the ''False'' object.
Any non-empty collection or string or non-zero numeric value is considered "True".
However, according to [http://wiki.python.org/moin/PythonSpeed#Takeadvantageofinterpreteroptimizations Python Wiki], for Python versions 2.3+ this variant is optimized by the interpreter and thus is the fastest.
## R
Note that the default R Gui buffers outputs before pushing them to the screen.
To see this run either run in terminal mode, right click on the GUI window and deselect "Buffered Output" prior to execution, or add a call to flush.console() in the loop.
```R
repeat print("SPAM")
```
## Racket
```racket
#lang racket
;; Using recursion
(define (loop)
(displayln "SPAM")
(loop))
(loop)
;; Using a for loop
(for ([i (in-naturals)])
(displayln "SPAM"))
```
## REBOL
```REBOL
forever [print "SPAM"]
```
## Red
```Red
forever [
print "SPAM"
]
```
## Retro
```Retro
[ "SPAM\n" puts -1 ] while
```
## REXX
### simple
```rexx
/*REXX program displays the word SPAM forever. */
do forever
say 'SPAM'
end /*DO forever*/
/*control will never reach here. */
/*don't stick a fork in it. */
```
### esoteric
```rexx
/*REXX program displays the word SPAM forever. */
do while 1==1 /*esoteric "forever" clause. */
say 'SPAM'
end /*DO while 1==1*/
/*control will never reach here. */
/*don't stick a fork in it. */
```
### GO TO version
```rexx
/*REXX program displays the word SPAM forever. */
tell_it: say 'SPAM'
signal tell_it /*REXX's version of a GO TO */
/*control will never reach here. */
/*don't stick a fork in it. */
```
### too clever by half
```rexx
/*REXX program displays the word SPAM forever. */
do until 0>1 /*too-clever-by-half forever loop*/
say 'SPAM'
end /*DO until 0>1*/
/*control will never reach here. */
/*don't stick a fork in it. */
```
## Ring
```ring
while true
see "Spam"
end
```
## Robotic
This will display the word '''SPAM''' at the bottom of the screen indefinitely:
```robotic
: "infinite_loop"
* "SPAM"
goto "infinite_loop"
```
## Ruby
```ruby
loop {puts "SPAM"}
```
## Rust
```rust
fn main() {
loop {
println!("SPAM");
}
}
```
## Run BASIC
```runbasic
[loop] print "Spam" :goto [loop]
while 1
print "Spam"
wend
```
=={{header|S-lang}}==
forever print("SPAM");
```
## Salmon
```Salmon
while (true)
"SPAM"!;
```
## Sather
```sather
class MAIN is
main is
loop
#OUT + "Spam\n";
end;
end;
end;
```
## Scala
```scala
while (true)
println("SPAM")
```
## Scheme
```scheme
((lambda (x) (display "SPAM") (newline) (x x))
(lambda (x) (display "SPAM") (newline) (x x)))
```
or, less Schemishly but with less redundancy:
```scheme
(do () (#f) (display "SPAM") (newline))
```
## Scilab
{{works with|Scilab|5.5.1}}
while %T
printf("SPAM\n")
end
```
{{out}}
```txt
SPAM
SPAM
SPAM
SPAM
...
```
## sed
```sed
:loop
s/.*/SPAM/
p
t loop
```
Sed requires at least one line of input to execute, so run as follows:
```txt
echo | sed ':loop;s/.*/SPAM/;p;t loop'
```
## Seed7
```seed7
$ include "seed7_05.s7i";
const proc: main is func
begin
while TRUE do
writeln("SPAM");
end while;
end func;
```
## Self
```self
['SPAM' printLine] loop
```
## Sidef
```ruby
loop { say "SPAM!" };
```
## Slate
```slate
[inform: 'SPAM'] loop
```
## Smalltalk
```smalltalk
[ true ] whileTrue: [ 'SPAM' displayNl ]
```
## SNOBOL4
```snobol
loop output = "SPAM" :(loop)
end
```
## SNUSP
```snusp>@\>@\>@\>@\
++++++++++===!/ < < < < \
| | | \M=@@@@+@+++++# \.>.>.>.>./
| | \A=@@+@@@@+++#
| \P=@@+@@+@@+++#
\S=@@+@+@@@+++#
```
## Sparkling
```sparkling
while true {
print("SPAM");
}
```
or
```sparkling
do {
print("SPAM");
} while true;
```
or
```sparkling
for var b = true; b; b = true {
printf("SPAM\n");
}
```
etc.
## Spin
{{works with|BST/BSTC}}
{{works with|FastSpin/FlexSpin}}
{{works with|HomeSpun}}
{{works with|OpenSpin}}
```spin
con
_clkmode = xtal1 + pll16x
_clkfreq = 80_000_000
obj
ser : "FullDuplexSerial.spin"
pub main
ser.start(31, 30, 0, 115200)
repeat
ser.str(string("SPAM",13,10))
waitcnt(_clkfreq + cnt)
ser.stop
cogstop(0)
```
## SPL
```spl>
#.output("SPAM")
<
```
## Standard ML
```sml
while true do
print "SPAM\n";
```
or
```sml
let
fun inf_loop () = (
print "SPAM\n";
inf_loop ()
)
in
inf_loop ()
end
```
Seen like this it looks like the "too much functional" danger when a "while" loop looks far simpler, but the functional loop may be useful to provide data to the next loop without using mutable variable.
## Stata
```stata
while 1 {
display "SPAM"
}
```
### Mata
```stata
while (1) printf("SPAM\n")
```
Also possible with a '''[https://www.stata.com/help.cgi?m2_for for]''' loop, but unlike C, the middle expression is not optional:
```stata
for (;1;) printf("SPAM\n")
```
## SQL PL
{{works with|Db2 LUW}} version 9.7 or higher.
With SQL PL:
```sql pl
--#SET TERMINATOR @
SET SERVEROUTPUT ON@
BEGIN
DECLARE I SMALLINT DEFAULT 1;
WHILE (I = I) DO
CALL DBMS_OUTPUT.PUT_LINE('SPAM');
END WHILE;
END @
```
Output:
```txt
db2 -td@
db2 => SET SERVEROUTPUT ON@
db2 => BEGIN
...
db2 (cont.) => END @
DB21034E The command was processed as an SQL statement because it was not a
valid Command Line Processor command. During SQL processing it returned:
SQL20511N There is not enough available space in the "DBMS_OUTPUT" message
buffer. SQLSTATE=54035
SPAM
SPAM
SPAM
SPAM
...
```
## Swift
```swift
while true {
println("SPAM")
}
```
## SystemVerilog
```SystemVerilog
program main;
initial forever $display("SPAM");
endprogram
```
=={{header|Transact-SQL}}==
```sql
WHILE 1=1 BEGIN
PRINT "SPAM"
END
```
## Tcl
```tcl
while true {
puts SPAM
}
# or
for {} 1 {} {
puts SPAM
}
```
=={{header|TI-83 BASIC}}==
There are a few ways to achieve this in TI-83 BASIC
```ti83b
:Lbl 1
:Disp "SPAM
:Goto 1
```
Another way is by using a While loop
```ti83b
:While 1
:Disp "SPAM
:End
```
=={{header|TI-89 BASIC}}==
```ti89b
Loop
Disp "SPAM"
EndLoop
```
## TorqueScript
```Torque
While(1)
echo("SPAM");
```
## Trith
```trith
["SPAM" print] loop
```
## TUSCRIPT
TUSCRIPT has no infinite loop. 999999999 loops are the limit.
```tuscript
$$ MODE TUSCRIPT
LOOP/999999999
print "spam"
ENDLOOP
```
## UNIX Shell
{{works with|Bourne Shell}}
Use any of these loops:
```bash>while :; do echo SPAM; done yes SPAM WHILE loop with a condition that will always evaluate to true:
```lisp
(defun keep-printing-spam ()
(while t
(display "SPAM")
(newline) ) )
```
Although this idiom is very common (in many programming languages), however, it feels a bit like a misuse of a looping construct that is meant to be conditional. If an unconditional jump is really what we want, then that is what we have goto for; or rather, in XLISP we do not have goto (in so many words) but we can achieve the effect of it using tail recursion.
```lisp
(defun keep-printing-spam ()
(display "SPAM")
(newline)
(keep-printing-spam) )
```
## XPL0
```XPL0
code Text=12;
loop Text(0, "SPAM
")
```
## Z80 Assembly
Using the Amstrad CPC firmware:
```z80
org $4000
txt_output: equ $bb5a
start: ld hl,spam
print: ld a,(hl)
cp 0
jr z,start
call txt_output
inc hl
jr print
spam: defm "SPAM\r\n\0"
```
## zkl
```zkl
while(1) { println("SPAM") }
while(True){ println("SPAM") }
foreach _ in ([0..]){ println("SPAM") }
[0..].pump(Console.println,T(Void,"SPAM"));
[0..].pump(fcn{ println("SPAM") });
fcn{ println("SPAM"); return(self.fcn()) }(); // tail recursive lambda
```
{{omit from|GUISS}}