Case-sensitivity of identifiers
You are encouraged to solve this task according to the task description, using any language you may know.
Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, Samba and Bernie.
For a language that is lettercase insensitive, we get the following output:
There is just one dog named Bernie.
- Related task
11l
11l identifiers are case sensitive.
V dog = ‘Benjamin’
V Dog = ‘Samba’
V DOG = ‘Bernie’
print(‘The three dogs are named ’dog‘, ’Dog‘ and ’DOG‘.’)
Action!
PROC Main()
CHAR ARRAY dog="Bernie"
PrintF("There is just one dog named %S.",dog)
RETURN
- Output:
Screenshot from Atari 8-bit computer
There is just one dog named Bernie.
Ada
case insensitive
with Ada.Text_IO;
procedure Dogs is
Dog : String := "Bernie";
begin
Ada.Text_IO.Put_Line ("There is just one dog named " & DOG);
end Dogs;
Output:
There is just one dog named Bernie
Agena
Translation of Algol W. Agena is case sensitive, as this example demonstrates. Tested with Agena 2.9.5 Win32
scope
local dog := "Benjamin";
scope
local Dog := "Samba";
scope
local DOG := "Bernie";
if DOG <> Dog or DOG <> dog
then print( "The three dogs are named: " & dog & ", " & Dog & " and " & DOG )
else print( "There is just one dog named: " & DOG )
fi
epocs
epocs
epocs
- Output:
The three dogs are named: Benjamin, Samba and Bernie
Aime
text dog, Dog, DOG;
dog = "Benjamin";
Dog = "Samba";
DOG = "Bernie";
o_form("The three dogs are named ~, ~ and ~.\n", dog, Dog, DOG);
ALGOL 68
A joke code entry... :-) ¢ but the code does actually work!
File: Case-sensitivity_of_identifiers.a68
#!/usr/bin/a68g --script #
# -*- coding: utf-8 -*- #
STRING dog = "Benjamin";
OP D = (INT og)STRING: "Samba";
OP DOG = (INT gy)STRING: "Bernie";
INT og=~, gy=~;
main:(
printf(($"The three dogs are named "g", "g" and "g"."l$, dog, Dog, DOGgy));
0
)
Output:
The three dogs are named Benjamin, Samba and Bernie.
Alternative version.
Most recent implementations of Algol 68 use "upper stropping", the "keywords" are in upper case and the identifiers are an lower case. This precludes use of e.g. Dog or DOG as the name of a variable or constant.
However, depending on the "stropping" convention used and the implementation, Algol 68 can be case-sensitive. Rutgers ALGOL 68 uses quote stropping and allows both upper and lower case in identifiers and bold words. The standard bold words must be in lower-case.
'begin'
'string' dog = "Benjamin";
'begin'
'string' Dog = "Samba";
'begin'
'string' DOG = "Bernie";
'if' DOG /= Dog 'or' DOG /= dog
'then' print( ( "The three dogs are named: ", dog, ", ", Dog, " and ", DOG ) )
'else' print( ( "There is just one dog named: ", DOG ) )
'fi'
'end'
'end'
'end'
- Output:
The three dogs are named: Benjamin, Samba and Bernie
ALGOL W
Algol W identifiers are not case-sensitive but variable names in inner blocks can be the same as those in outer blocks...
begin
string(8) dog;
dog := "Benjamin";
begin
string(8) Dog;
Dog := "Samba";
begin
string(8) DOG;
DOG := "Bernie";
if DOG not = Dog
or DOG not = dog
then write( "The three dogs are named: ", dog, ", ", Dog, " and ", DOG )
else write( "There is just one dog named: ", DOG )
end
end
end.
- Output:
There is just one dog named: Bernie
APL
DOG←'Benjamin'
Dog←'Samba'
dog←'Bernie'
'The three dogs are named ',DOG,', ',Dog,', and ',dog
The three dogs are named Benjamin, Samba, and Bernie
Arturo
dog: "Benjamin"
Dog: "Samba"
DOG: "Bernie"
dogs: @[dog Dog DOG]
print ["The" size dogs "dog(s) are named" join.with:", " dogs]
- Output:
The 3 dog(s) are named Benjamin, Samba, Bernie
AutoHotkey
dog := "Benjamin"
Dog := "Samba"
DOG := "Bernie"
MsgBox There is just one dog named %dOG%
AWK
BEGIN {
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
printf "The three dogs are named %s, %s and %s.\n", dog, Dog, DOG
}
The three dogs are named Benjamin, Samba and Bernie.
BASIC
QBASIC is case-insensitive
DOG$ = "Benjamin"
DOG$ = "Samba"
DOG$ = "Bernie"
PRINT "There is just one dog, named "; DOG$
BASIC256
BASIC256 is case-insensitive
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
print "There is just one dog, named "; dog
end
Batch File
@echo off
set dog=Benjamin
set Dog=Samba
set DOG=Bernie
echo There is just one dog named %dog%.
pause>nul
- Output:
There is just one dog named Bernie.
BBC BASIC
dog$ = "Benjamin"
Dog$ = "Samba"
DOG$ = "Bernie"
PRINT "The three dogs are " dog$ ", " Dog$ " and " DOG$ "."
Output:
The three dogs are Benjamin, Samba and Bernie.
bc
The only variables are 'a' through 'z'. They can only hold numbers, not strings. Some implementations allow longer names like 'dog', but only with lowercase letters. A name like 'Dog' or 'DOG' is a syntax error.
obase = 16
ibase = 16
/*
* Store the hexadecimal number 'BE27A312'
* in the variable 'd'.
*/
d = BE27A312
"There is just one dog named "; d
quit
There is just one dog named BE27A312
Bracmat
( Benjamin:?dog
& Samba:?Dog
& Bernie:?DOG
& out$("There are three dogs:" !dog !Dog and !DOG)
);
Output:
There are three dogs: Benjamin Samba and Bernie
Brlcad
The three dogs are drawn as spheres in this simple example:
opendb dogs.g y # Create a database to hold our dogs
units ft # The dogs are measured in feet
in dog.s sph 0 0 0 1 # Benjie is a little Scottie dog
in Dog.s sph 4 0 0 3 # Samba is a Labrador
in DOG.s sph 13 0 0 5 # Bernie is massive. He is a New Foundland
echo The three dogs are named Benjamin, Samba and Bernie
C
C is case sensitive; if it would be case insensitive, an error about redefinition of a variable would be raised.
#include <stdio.h>
static const char *dog = "Benjamin";
static const char *Dog = "Samba";
static const char *DOG = "Bernie";
int main()
{
printf("The three dogs are named %s, %s and %s.\n", dog, Dog, DOG);
return 0;
}
C#
C# is case sensitive
using System;
class Program
{
static void Main(string[] args)
{
string dog = "Benjamin";
string Dog = "Samba";
string DOG = "Bernie";
Console.WriteLine(string.Format("The three dogs are named {0}, {1}, and {2}.", dog, Dog, DOG));
}
}
C++
C++ is case-sensitive.
#include <iostream>
#include <string>
using namespace std;
int main() {
string dog = "Benjamin", Dog = "Samba", DOG = "Bernie";
cout << "The three dogs are named " << dog << ", " << Dog << ", and " << DOG << endl;
}
- Output:
The three dogs are named Benjamin, Samba, and Bernie
Clojure
user=> (let [dog "Benjamin" Dog "Samba" DOG "Bernie"] (format "The three dogs are named %s, %s and %s." dog Dog DOG)) "The three dogs are named Benjamin, Samba and Bernie."
COBOL
* Case sensitivity of identifiers
*>* Commented-out lines in the working storage
*>* are considered as invalid redefinitions
*>* of ''dog'' that can only be ambiguously
*>* referenced in the procedure body.
IDENTIFICATION DIVISION.
PROGRAM-ID. case-sensitivity.
DATA DIVISION.
WORKING-STORAGE SECTION.
*>* 01 dog PICTURE X(8) VALUE IS "Benjamin".
*>* 01 Dog PICTURE X(5) VALUE IS "Samba".
01 DOG PICTURE X(6) VALUE IS "Bernie".
PROCEDURE DIVISION.
DISPLAY
*>* "The three dogs are named "
*>* dog ", " Dog " and " DOG "."
"There is just one dog named " DOG "."
END-DISPLAY
STOP RUN.
END PROGRAM case-sensitivity.
CoffeeScript
dog="Benjamin"
Dog = "Samba"
DOG = "Bernie"
console.log "The three dogs are names #{dog}, #{Dog}, and #{DOG}."
output
> coffee foo.coffee
The three dogs are names Benjamin, Samba, and Bernie.
Common Lisp
CL-USER> (let* ((dog "Benjamin") (Dog "Samba") (DOG "Bernie"))
(format nil "There is just one dog named ~a." dog))
; in: LAMBDA NIL
; (LET* ((DOG "Benjamin") (DOG "Samba") (DOG "Bernie"))
; (FORMAT NIL "There is just one dog named ~a." DOG))
;
; caught STYLE-WARNING:
; The variable DOG is defined but never used.
;
; caught STYLE-WARNING:
; The variable DOG is defined but never used.
;
; compilation unit finished
; caught 2 STYLE-WARNING conditions
"There is just one dog named Bernie."
These are the style warnings from SBCL. Other implementations of Common Lisp might give different warnings.
Crystal
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
puts "The three dogs are named #{dog}, #{Dog} and #{DOG}."
Note that in Crystal, variables with all-caps identifiers (like DOG
) are always constants.
- Output:
The three dogs are named Benjamin, Samba and Bernie.
D
import std.stdio;
void main() {
string dog = "Benjamin";
// identifiers that start with capital letters are type names
string Dog = "Samba";
string DOG = "Bernie";
writefln("There are three dogs named ",
dog, ", ", Dog, ", and ", DOG, "'");
}
Output:
There are three dogs named Benjamin, Samba, and Bernie'
dc
A register name has only one character, so this example uses 'd' and 'D'.
[Benjamin]sd
[Samba]sD
[The two dogs are named ]P ldP [ and ]P lDP [.
]P
- Output:
The two dogs are named Benjamin and Samba.
Delphi
Delphi is case insensitive.
program CaseSensitiveIdentifiers;
{$APPTYPE CONSOLE}
var
dog: string;
begin
dog := 'Benjamin';
Dog := 'Samba';
DOG := 'Bernie';
Writeln('There is just one dog named ' + dog);
end.
Output:
There is just one dog named Bernie
DWScript
var dog : String;
dog := 'Benjamin';
Dog := 'Samba';
DOG := 'Bernie';
PrintLn('There is just one dog named ' + dog);
Output:
There is just one dog named Bernie
Déjà Vu
local :dog "Benjamin"
local :Dog "Samba"
local :DOG "Bernie"
!print( "There are three dogs named " dog ", " Dog " and " DOG "." )
- Output:
There are three dogs named Benjamin, Samba and Bernie.
EasyLang
EasyLang is case-sensitive.
dog$ = "Benjamin"
Dog$ = "Samba"
DOG$ = "Bernie"
#
print "The three dogs are named " & dog$ & ", " & Dog$ & ", and " & DOG$ & "."
EchoLisp
(define dog "Benjamin")
(define Dog "Samba")
(define DOG "Bernie")
(printf "The three dogs are named %a, %a and %a. " dog Dog DOG)
The three dogs are named Benjamin, Samba and Bernie.
Ecstasy
String dog = "Benjamin"; // by convention, variable and property names use lower camelCase
String Dog = "Samba"; // by convention, upper CamelCase is used for class, type, and constant names
String DOG = "Bernie"; // by convention, all-caps is only used for constants
@Inject Console console;
console.println($"There are three dogs named {dog}, {Dog}, and {DOG}");
Elena
In ELENA identifiers are case sensitive. ELENA 4.x:
import extensions;
public program()
{
var dog := "Benjamin";
var Dog := "Samba";
var DOG := "Bernie";
console.printLineFormatted("The three dogs are named {0}, {1} and {2}", dog, Dog, DOG)
}
- Output:
The three dogs are named Benjamin, Samba and Bernie
Elixir
While Elixir's identifiers are case-sensitive, they generally must start with a lowercase letter. Capitalized identifiers are reserved for modules.
dog = "Benjamin"
doG = "Samba"
dOG = "Bernie"
IO.puts "The three dogs are named #{dog}, #{doG} and #{dOG}."
- Output:
The three dogs are named Benjamin, Samba and Bernie.
Erlang
Erlang variables are case sensitive but must start with an uppercase letter.
-module( case_sensitivity_of_identifiers ).
-export( [task/0] ).
task() ->
catch dog = "Benjamin", % Function will crash without catch
Dog = "Samba",
DOG = "Bernie",
io:fwrite( "The three dogs are named ~s, ~s and ~s~n", [dog, Dog, DOG] ).
- Output:
4> case_sensitivity_of_identifiers:task(). The three dogs are named dog, Samba and Bernie
Euphoria
-- These variables are all different
sequence dog = "Benjamin"
sequence Dog = "Samba"
sequence DOG = "Bernie"
printf( 1, "The three dogs are named %s, %s and %s\n", {dog, Dog, DOG} )
F#
F# is case-sensitive.
let dog = "Benjamin"
let Dog = "Samba"
let DOG = "Bernie"
printfn "There are three dogs named %s, %s and %s" dog Dog DOG
Factor
Factor identifiers are case-sensitive.
USING: formatting locals ;
IN: scratchpad
[let
"Benjamin" :> dog
"Samba" :> Dog
"Bernie" :> DOG
{ dog Dog DOG } "There are three dogs named %s, %s, and %s." vprintf
]
- Output:
There are three dogs named Benjamin, Samba, and Bernie.
Forth
: DOG ." Benjamin" ;
: Dog ." Samba" ;
: dog ." Bernie" ;
: HOWMANYDOGS ." There is just one dog named " DOG ;
HOWMANYDOGS
- Output:
There is just one dog named Bernie
Fortran
Fortran is case insensitive, and so the three "dog" variants name the same variable - which therefore is multiply declared and will likely evoke a compiler complaint.
program Example
implicit none
character(8) :: dog, Dog, DOG
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
if (dog == DOG) then
write(*,*) "There is just one dog named ", dog
else
write(*,*) "The three dogs are named ", dog, Dog, " and ", DOG
end if
end program Example
Output:
There is just one dog named Bernie
FreeBASIC
' FB 1.05.0 Win64
' FreeBASIC is case-insensitive
Dim dog As String
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
Print "There is just one dog, named "; dog
Sleep
- Output:
There is just one dog, named Bernie
Frink
Frink is case-sensitive.
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
println["There are three dogs named $dog, $Dog and $DOG"]
FutureBasic
FB is lettercase-insensitive and throws an error with variables or constants with identical names but of varying case. However, here's an easy work around.
CFDictionaryRef canines
canines = @{@"dog":@"Benjamin", @"Dog":@"Samba", @"DOG":@"Bernie"}
print "The three dogs are "; canines[@"dog"]; ", "; canines[@"Dog"]; " and "; canines[@"DOG"]; "."
HandleEvents
- Output:
There are three dogs named Benjamin, Samba and Bernie.
Gambas
Click this link to run this code
Gambas in case insensitive
Public Sub Main()
Dim dog As String
Dog = "Benjamin"
DOG = "Samba"
dog = "Bernie"
Print "There is just one dog, named "; dog
End
Output:
There is just one dog, named Bernie
GAP
# GAP is case sensitive
ThreeDogs := function()
local dog, Dog, DOG;
dog := "Benjamin";
Dog := "Samba";
DOG := "Bernie";
if dog = DOG then
Print("There is just one dog named ", dog, "\n");
else
Print("The three dogs are named ", dog, ", ", Dog, " and ", DOG, "\n");
fi;
end;
ThreeDogs();
# The three dogs are named Benjamin, Samba and Bernie
Go
Go is case sensitive. Further, visibility depends on case. See the Go entry under the Scope modifiers task.
package dogs
import "fmt"
// Three variables, three different names.
// (It wouldn't compile if the compiler saw the variable names as the same.)
var dog = "Salt"
var Dog = "Pepper"
var DOG = "Mustard"
func PackageSees() map[*string]int {
// Print dogs visible from here.
fmt.Println("Package sees:", dog, Dog, DOG)
// Return addresses of the variables visible from here.
// The point of putting them in a map is that maps store only
// unique keys, so it will end up with three items only if
// the variables really represent different places in memory.
return map[*string]int{&dog: 1, &Dog: 1, &DOG: 1}
}
package main
import (
. "dogs"
"fmt"
)
func main() {
// with the dogs package imported, there are three dogs.
d := PackageSees()
fmt.Println("There are", len(d), "dogs.\n")
// Declaration of new variable dog. It lives in this package, main.
dog := "Benjamin"
d = PackageSees()
fmt.Println("Main sees: ", dog, Dog, DOG)
// Four dogs now. two of the three visible from here are the
// the same as ones in the dogs package.
d[&dog] = 1
d[&Dog] = 1
d[&DOG] = 1
fmt.Println("There are", len(d), "dogs.\n")
// Not a declaration, just an assigment. This assigns a new value to
// the variable Dog declared in the package. Dog is visible because
// it begins with an upper case letter.
Dog = "Samba"
// same four dogs, same three visible, one just has a new name.
d = PackageSees()
fmt.Println("Main sees: ", dog, Dog, DOG)
d[&dog] = 1
d[&Dog] = 1
d[&DOG] = 1
fmt.Println("There are", len(d), "dogs.\n")
// Of course you can still declare a variable if you want to. This
// declares a new variable, shadowing DOG in the package and rendering
// it inaccessable even though it begins with an upper case letter.
var DOG = "Bernie"
// five dogs now. three visible from here.
d = PackageSees()
fmt.Println("Main sees: ", dog, Dog, DOG)
d[&dog] = 1
d[&Dog] = 1
d[&DOG] = 1
fmt.Println("There are", len(d), "dogs.")
}
- Output:
Package sees: Salt Pepper Mustard There are 3 dogs. Package sees: Salt Pepper Mustard Main sees: Benjamin Pepper Mustard There are 4 dogs. Package sees: Salt Samba Mustard Main sees: Benjamin Samba Mustard There are 4 dogs. Package sees: Salt Samba Mustard Main sees: Benjamin Samba Bernie There are 5 dogs.
Groovy
Solution:
def dog = "Benjamin", Dog = "Samba", DOG = "Bernie"
println (dog == DOG ? "There is one dog named ${dog}" : "There are three dogs named ${dog}, ${Dog} and ${DOG}.")
Output:
There are three dogs named Benjamin, Samba and Bernie.
Haskell
Identifiers are case sensitive in Haskell, but must start with a lower case letter.
import Text.Printf
main = printf "The three dogs are named %s, %s and %s.\n" dog dOG dOg
where dog = "Benjamin"
dOG = "Samba"
dOg = "Bernie"
Icon and Unicon
The program below demonstrates the three dog task. All variants of Icon/Unicon have case sensitive variable names. But if one wasn't this would find it.
J
NB. These variables are all different
dog=: 'Benjamin'
Dog=: 'Samba'
DOG=: 'Bernie'
'The three dogs are named ',dog,', ',Dog,', and ',DOG
The three dogs are named Benjamin, Samba, and Bernie
Java
String dog = "Benjamin";
String Dog = "Samba"; //in general, identifiers that start with capital letters are class names
String DOG = "Bernie"; //in general, identifiers in all caps are constants
//the conventions listed in comments here are not enforced by the language
System.out.println("There are three dogs named " + dog + ", " + Dog + ", and " + DOG + "'");
JavaScript
Javascript is case sensitive.
var dog = "Benjamin";
var Dog = "Samba";
var DOG = "Bernie";
document.write("The three dogs are named " + dog + ", " + Dog + ", and " + DOG + ".");
jq
jq identifiers are case-sensitive.
Function parameters:
def task(dog; Dog; DOG):
"The three dogs are named \(dog), \(Dog), and \(DOG)." ;
task("Benjamin"; "Samba"; "Bernie")
- Output:
$ jq -n -f Case-sensitivity.jq "The three dogs are named Benjamin, Samba, and Bernie."
Variable names:
"Benjamin" as $dog | "Samba" as $Dog | "Bernie" as $DOG
| "The three dogs are named \($dog), \($Dog), and \($DOG)."
- Output:
As above.
Julia
Variable names are case sensitive.
dog, Dog, DOG = "Benjamin", "Samba", "Bernie"
if dog === Dog
println("There is only one dog, ", DOG)
else
println("The three dogs are: ", dog, ", ", Dog, " and ", DOG)
end
- Output:
The three dogs are: Benjamin, Samba and Bernie
Conventionally, variable names should be all lower case. Type and Macro names should be capitalized.
K
dog: "Benjamin"
Dog: "Samba"
DOG: "Bernie"
"There are three dogs named ",dog,", ",Dog," and ",DOG
"There are three dogs named Benjamin, Samba and Bernie"
Kotlin
Kotlin is case-sensitive though (as in Java) the convention is for local variable names to begin with a lower case letter. The second and third identifiers would therefore be unlikely to be used in practice.
fun main(args: Array<String>) {
val dog = "Benjamin"
val Dog = "Samba"
val DOG = "Bernie"
println("The three dogs are named $dog, $Dog and $DOG")
}
- Output:
The three dogs are named Benjamin, Samba and Bernie
Lasso
Lasso is not case sensitive for names
local(dog = 'Benjamin')
local(Dog = 'Samba')
local(DOG = 'Bernie')
stdoutnl('There is just one dog named ' + #dog)
Output:
There is just one dog named Bernie
Same with string comparisons. (Lasso maps can only contain unique keys)
local(dogs = map(
'dog' = 'Benjamin',
'Dog' = 'Samba',
'DOG' = 'Bernie'
))
stdoutnl(#dogs -> size)
Output:
1
To get case sensitivity we need to use bytes
local(dogs = map(
bytes('dog') = 'Benjamin',
bytes('Dog') = 'Samba',
bytes('DOG') = 'Bernie'
))
stdoutnl(#dogs -> size)
stdoutnl(#dogs -> find(bytes('Dog')))
Output:
3 Samba
Liberty BASIC
NB the IDE warns you that there are similar variables named dog$, Dog$ & DOG$
dog$ = "Benjamin"
Dog$ = "Samba"
DOG$ = "Bernie"
print "The three dogs are "; dog$; ", "; Dog$; " and "; DOG$; "."
end
The three dogs are Benjamin, Samba and Bernie.
Lua
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
print( "There are three dogs named "..dog..", "..Dog.." and "..DOG.."." )
There are three dogs named Benjamin, Samba and Bernie.
M2000 Interpreter
Labels are case sensitive, but identifiers are not case sensitive. Keys in Inventory are case sensitive Types in Enumeration are case sensitive, identifiers are not case sensitive.
MoDuLe CheckIT {
\\ keys as case sensitive if they are strings
Inventory A= "Dog":=1, "dog":=2,"DOG":="Hello", 100:="Dog"
Print A("Dog"), A("dog"), A$("DOG"), A$(100)
\\ Enumeration get type as defined (same case)
Enum Dogs {Benjamin, Samba, Bernie}
Print Type$(Bernie)="Dogs"
Print Type$(DOGS)="Dogs"
m=BenJamiN
m++
Print Eval$(m)="Samba" ' same case as defined
DoG$="Benjamin"
DOG$="Samba"
doG$="Bernie"
PrinT "There is just one dog named "+Dog$+"."
goto Dog
dog:
Print "dog"
Exit
Dog:
Print "Dog"
GoTo dog
}
Checkit
Maple
> dog, Dog, DOG := "Benjamin", "Samba", "Bernie":
> if nops( { dog, Dog, DOG } ) = 3 then
> printf( "There are three dogs named %s, %s and %s.\n", dog, Dog, DOG )
> elif nops( { dog, Dog, DOG } ) = 2 then
> printf( "WTF? There are two dogs named %s and %s.\n", op( { dog, Dog, DOG } ) )
> else
> printf( "There is one dog named %s.\n", dog )
> end if:
There are three dogs named Benjamin, Samba and Bernie.
Mathematica / Wolfram Language
dog = "Benjamin"; Dog = "Samba"; DOG = "Bernie";
"The three dogs are named "<> dog <>", "<> Dog <>" and "<> DOG
-> "The three dogs are named Benjamin, Samba and Bernie"
MATLAB / Octave
dog = 'Benjamin';
Dog = 'Samba';
DOG = 'Bernie';
printf('There are three dogs %s, %s, %s.\n',dog, Dog, DOG);
Output
There are three dogs Benjamin, Samba, Bernie.
Maxima
/* Maxima is case sensitive */
a: 1$
A: 2$
is(a = A);
false
min
min's symbols are case sensitive.
"Benjamin" :dog
"Samba" :Dog
"Bernie" :DOG
"There are three dogs named $1, $2, and $3." (dog Dog DOG)=> % print
- Output:
There are three dogs named Benjamin, Samba, and Bernie.
MiniScript
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
print "There are three dogs named " + dog + ", " + Dog + " and " + DOG
Modula-2
MODULE dog;
IMPORT InOut;
TYPE String = ARRAY [0..31] OF CHAR;
VAR dog, Dog, DOG : String;
(* No compiler error, so the rest is simple *)
BEGIN
InOut.WriteString ("Three happy dogs.");
InOut.WriteLn
END dog.
Nanoquery
dog = "Benjamin"
Dog = "Samba"
DOG = "Bernie"
print format("The three dogs are named %s, %s, and %s.\n", dog, Dog, DOG)
- Output:
The three dogs are named Benjamin, Samba, and Bernie.
Nemerle
def dog = "Benjamin";
def Dog = "Samba";
def DOG = "Bernie";
WriteLine($"The three dogs are named $dog, $Dog, and $DOG");
NESL
NESL is completely case-insensitive.
dog = "Benjamin";
Dog = "Samba";
DOG = "Bernie";
"There is just one dog, named " ++ dog;
- Output:
it = "There is just one dog, named Bernie" : [char]
NetRexx
NetRexx is not case sensitive:
/* NetRexx */
options replace format comments java crossref symbols nobinary
dog = "Benjamin";
Dog = "Samba";
DOG = "Bernie";
if dog == Dog & Dog == DOG & dog == DOG then do
say 'There is just one dog named' dog'.'
end
else do
say 'The three dogs are named' dog',' Dog 'and' DOG'.'
end
return
Output:
There is just one dog named Bernie.
Nim
Nim has peculiar rules regarding case and style sensitivity:
- – it is mainly a case insensitive language;
- – but keywords are all in lowercase;
- – and the first letter of an identifier is case sensitive;
- – moreover, underline is ignored in identifiers (style insensitivity).
With these rules, we don’t get one dog or three dogs: we get two dogs!
var dog, Dog: string
(dog, Dog, DOG) = ("Benjamin", "Samba", "Bernie")
if dog == Dog:
if dog == DOG:
echo "There is only one dog, ", DOG)
else:
echo "There are two dogs: ", dog, " and ", DOG
elif Dog == DOG :
echo "There are two dogs: ", dog, " and ", DOG
else:
echo "There are three dogs: ", dog, ", ", Dog, " and ", DOG
- Output:
There are two dogs: Benjamin and Bernie
Oberon-2
MODULE CaseSensitivity;
IMPORT
Out;
VAR
dog, Dog, DOG: STRING;
BEGIN
dog := "Benjamin";
Dog := "Samba";
DOG := "Bernie";
Out.Object("The three dogs are named " + dog + ", " + Dog + " and " + DOG);
Out.Ln
END CaseSensitivity.
- Output:
The three dogs are named Benjamin, Samba and Bernie
Objeck
Objeck is case sensitive
class Program {
function : Main(args : String[]) ~ Nil {
dog := "Benjamin";
Dog := "Samba";
DOG := "Bernie";
"The three dogs are named {$dog}, {$Dog}, and {$DOG}."->PrintLine();
}
}
OCaml
Identifiers in OCaml are lettercase sensitive, but the first letter has to be lowercase.
let () =
let dog = "Benjamin" in
let dOG = "Samba" in
let dOg = "Bernie" in
Printf.printf "The three dogs are named %s, %s and %s.\n" dog dOG dOg
Oforth
Oforth is case-sensitive.
: threeDogs
| dog Dog DOG |
"Benjamin" ->dog
"Samba" ->Dog
"Bernie" ->DOG
System.Out "The three dogs are named " << dog << ", " << Dog << " and " << DOG << "." << cr ;
Ol
(define dog "Benjamin")
(define Dog "Samba")
(define DOG "Bernie")
(print "The three dogs are named " dog ", " Dog " and " DOG ".\n")
- Output:
The three dogs are named Benjamin, Samba and Bernie.
PARI/GP
dog="Benjamin";
Dog="Samba";
DOG="Bernie";
printf("The three dogs are named %s, %s, and %s.", dog, Dog, DOG)
Pascal
See Delphi
Perl
# These variables are all different
$dog='Benjamin';
$Dog='Samba';
$DOG='Bernie';
print "The three dogs are named $dog, $Dog, and $DOG \n"
Phix
Phix is case sensitive
sequence dog = "Benjamin", Dog = "Samba", DOG = "Bernie" printf( 1, "The three dogs are named %s, %s and %s\n", {dog, Dog, DOG} )
- Output:
The three dogs are named Benjamin, Samba and Bernie
PicoLisp
(let (dog "Benjamin" Dog "Samba" DOG "Bernie")
(prinl "The three dogs are named " dog ", " Dog " and " DOG) )
Output:
The three dogs are named Benjamin, Samba and Bernie
PL/I
*process or(!) source xref attributes macro options;
/*********************************************************************
* Program to show that PL/I is case-insensitive
* 28.05.2013 Walter Pachl
*********************************************************************/
case: proc options(main);
Dcl dog Char(20) Var;
dog = "Benjamin";
Dog = "Samba";
DOG = "Bernie";
Put Edit(dog,Dog,DOG)(Skip,3(a,x(1)));
End;
Output
Bernie Bernie Berni
Plain English
Plain English is NOT case sensitive.
To run:
Start up.
Put "Benjamin" into a DOG string.
Put "Samba" into the Dog string.
Put "Bernie" into the dog string.
Write "There is just one dog named " then the DOG on the console.
Wait for the escape key.
Shut down.
- Output:
There is just one dog named Bernie
PowerShell
PowerShell is not case sensitive.
$dog = "Benjamin"
$Dog = "Samba"
$DOG = "Bernie"
"There is just one dog named {0}." -f $dOg
- Output:
There is just one dog named Bernie.
Prolog
In Prolog, the initial of a variable must be a uppercase letter. So the task can't be completed but we can write this code :
three_dogs :-
DoG = 'Benjamin',
Dog = 'Samba',
DOG = 'Bernie',
format('The three dogs are named ~w, ~w and ~w.~n', [DoG, Dog, DOG]).
The output is :
?- three_dogs. The three dogs are named Benjamin, Samba and Bernie. true.
PureBasic
dog$="Benjamin"
Dog$="Samba"
DOG$="Bernie"
Debug "There is just one dog named "+dog$
Python
Python names are case sensitive:
>>> dog = 'Benjamin'; Dog = 'Samba'; DOG = 'Bernie'
>>> print ('The three dogs are named ',dog,', ',Dog,', and ',DOG)
The three dogs are named Benjamin , Samba , and Bernie
>>>
Quackery
[ $ 'Benjamin' ] is dog ( --> $ )
[ $ 'Samba' ] is Dog ( --> $ )
[ $ 'Bernie' ] is DOG ( --> $ )
say 'There are three dogs named '
dog echo$ say ', '
Dog echo$ say ', and '
DOG echo$ say '.' cr
- Output:
There are three dogs named Benjamin, Samba, and Bernie.
R
dog <- 'Benjamin'
Dog <- 'Samba'
DOG <- 'Bernie'
# Having fun with cats and dogs
cat('The three dogs are named ')
cat(dog)
cat(', ')
cat(Dog)
cat(' and ')
cat(DOG)
cat('.\n')
# In one line it would be:
# cat('The three dogs are named ', dog, ', ', Dog, ' and ', DOG, '.\n', sep = '')
Output:
The three dogs are named Benjamin, Samba and Bernie.
Racket
The default setting for the Racket reader is to be case sensitive:
#lang racket
(define dog "Benjamin")
(define Dog "Samba")
(define DOG "Bernie")
(if (equal? dog DOG)
(displayln (~a "There is one dog named " DOG "."))
(displayln (~a "The three dogs are named " dog ", " Dog ", and, " DOG ".")))
Output:
The three dogs are named Benjamin, Samba, and, Bernie.
If you need case insensitive identifiers, then use #ci to turn on case insensitivity:
#lang racket
#ci(module dogs racket
(define dog "Benjamin")
(set! Dog "Samba")
(set! DOG "Bernie")
(if (equal? dog DOG)
(displayln (~a "There is one dog named " DOG "."))
(displayln (~a "The three dogs are named " dog ", " Dog ", and, " DOG "."))))
(require 'dogs)
Output:
There is one dog named Bernie.
Raku
(formerly Perl 6)
my $dog = 'Benjamin';
my $Dog = 'Samba';
my $DOG = 'Bernie';
say "The three dogs are named $dog, $Dog, and $DOG."
The only place that Raku pays any attention to the case of identifiers is that, for certain error messages, it will guess that an identifier starting lowercase is probably a function name, while one starting uppercase is probably a type or constant name. But this case distinction is merely a convention in Raku, not mandatory:
constant dog = 'Benjamin';
sub Dog() { 'Samba' }
my &DOG = { 'Bernie' }
say "The three dogs are named {dog}, {Dog}, and {DOG}."
Retro
Retro is case sensitive.
: dog ( -$ ) "Benjamin" ;
: Dog ( -$ ) "Samba" ;
: DOG ( -$ ) "Bernie" ;
DOG Dog dog "The three dogs are named %s, %s, and %s.\n" puts
REXX
simple variables
The REXX language is case insensitive (with respect to simple variables).
/*REXX program demonstrate case insensitivity for simple REXX variable names. */
/* ┌──◄── all 3 left─hand side REXX variables are identical (as far as assignments). */
/* │ */
/* ↓ */
dog= 'Benjamin' /*assign a lowercase variable (dog)*/
Dog= 'Samba' /* " " capitalized " Dog */
DOG= 'Bernie' /* " an uppercase " DOG */
say center('using simple variables', 35, "─") /*title.*/
say
if dog\==Dog | DOG\==dog then say 'The three dogs are named:' dog"," Dog 'and' DOG"."
else say 'There is just one dog named:' dog"."
/*stick a fork in it, we're all done. */
output
──────using simple variables─────── There is just one dog named: Bernie.
compound variables
However, the REXX language is case sensitive (with respect to compound variables, or indices).
/*REXX program demonstrate case sensitive REXX index names (for compound variables). */
/* ┌──◄── all 3 indices (for an array variable) are unique (as far as array index). */
/* │ */
/* ↓ */
x= 'dog'; dogname.x= "Gunner" /*assign an array index, lowercase dog*/
x= 'Dog'; dogname.x= "Thor" /* " " " " capitalized Dog*/
x= 'DOG'; dogname.x= "Jax" /* " " " " uppercase DOG*/
x= 'doG'; dogname.x= "Rex" /* " " " " mixed doG*/
say center('using compound variables', 35, "═") /*title.*/
say
_= 'dog'; say "dogname.dog=" dogname._ /*display an array index, lowercase dog*/
_= 'Dog'; say "dogname.Dog=" dogname._ /* " " " " capitalized Dog*/
_= 'DOG'; say "dogname.DOG=" dogname._ /* " " " " uppercase DOG*/
_= 'doG'; say "dogname.doG=" dogname._ /* " " " " mixed doG*/
/*stick a fork in it, we're all done. */
output
═════using compound variables══════ dogname.dog= Gunner dogname.Dog= Thor dogname.DOG= Jax dogname.doG= Rex
Ring
dog = "Benjamin"
doG = "Smokey"
Dog = "Samba"
DOG = "Bernie"
see "The 4 dogs are : " + dog + ", " + doG + ", " + Dog + " and " + DOG + "."
Ruby
Ruby gives a special meaning to the first letter of a name. A lowercase letter starts a local variable. An uppercase letter starts a constant. So dog is a local variable, but Dog and DOG are constants. To adapt this task to Ruby, I added dOg and doG so that I have more than one local variable.
module FiveDogs
dog = "Benjamin"
dOg = "Dogley"
doG = "Fido"
Dog = "Samba" # this constant is FiveDogs::Dog
DOG = "Bernie" # this constant is FiveDogs::DOG
names = [dog, dOg, doG, Dog, DOG]
names.uniq!
puts "There are %d dogs named %s." % [names.length, names.join(", ")]
puts
puts "The local variables are %s." % local_variables.join(", ")
puts "The constants are %s." % constants.join(", ")
end
Output:
There are 5 dogs named Benjamin, Dogley, Fido, Samba, Bernie. The local variables are dog, dOg, doG, names. The constants are Dog, DOG.
Run BASIC
dog$ = "Benjamin"
doG$ = "Smokey"
Dog$ = "Samba"
DOG$ = "Bernie"
print "The 4 dogs are "; dog$; ", "; doG$; ", "; Dog$; " and "; DOG$; "."
Rust
Rust style dictates that identifiers should be written in snake case, e.g. big_dog, small_dog; whereas types (structs and enums) should be written in camel case, e.g. BigDog, SmallDog. Failing to comply with this standard does not cause a compiler error, but it will trigger a compiler warning, and the culture is very strongly towards compliance with this standard.
fn main() {
let dog = "Benjamin";
let Dog = "Samba";
let DOG = "Bernie";
println!("The three dogs are named {}, {} and {}.", dog, Dog, DOG);
}
This triggers two warnings at compilation:
<anon>:3:9: 3:12 warning: variable `Dog` should have a snake case name such as `dog`, #[warn(non_snake_case)] on by default
<anon>:3 let Dog = "Samba";
^~~
<anon>:4:9: 4:12 warning: variable `DOG` should have a snake case name such as `dog`, #[warn(non_snake_case)] on by default
<anon>:4 let DOG = "Bernie";
^~~
The resulting program will compile and run just fine, producing the output:
The three dogs are named Benjamin, Samba and Bernie.
Sather
Though by convention Sather uses all uppercase letters for class names, a variable can be all uppercase.
class MAIN is
main is
dog ::= "Benjamin";
Dog ::= "Samba";
DOG ::= "Bernie";
#OUT + #FMT("The three dogs are %s, %s and %s\n",
dog, Dog, DOG);
end;
end;
Outputs:
The three dogs are Benjamin, Samba and Bernie
Scala
val dog = "Benjamin"
val Dog = "Samba"
val DOG = "Bernie"
println("There are three dogs named " + dog + ", " + Dog + ", and " + DOG + ".")
Output:
There are three dogs named Benjamin, Samba, and Bernie.
Scheme
Output may differ depending on implementation.
(define dog "Benjamin")
(define Dog "Samba")
(define DOG "Bernie")
(if (eq? dog DOG)
(begin (display "There is one dog named ")
(display DOG)
(display ".")
(newline))
(begin (display "The three dogs are named ")
(display dog) (display ", ")
(display Dog) (display " and ")
(display DOG)
(display ".")
(newline)))
Seed7
$ include "seed7_05.s7i";
const string: dog is "Benjamin";
const string: Dog is "Samba";
const string: DOG is "Bernie";
const proc: main is func
begin
writeln("The three dogs are named " <& dog <& ", " <& Dog <& " and " <& DOG <& ".");
end func;
SenseTalk
As a People Oriented Programming language, SenseTalk's variable names are case-insensitive.
set dog to "Benjamin"
set Dog to "Samba"
set DOG to "Bernie"
put !"There is just one dog named [[dog]]."
- Output:
There is just one dog named Bernie.
SETL
dog := 'Benjamin';
Dog := 'Samba';
DOG := 'Bernie';
print( 'There is just one dog named', dOg );
- Output:
There is just one dog named Bernie
Sidef
var dog = 'Benjamin';
var Dog = 'Samba';
var DOG = 'Bernie';
say "The three dogs are named #{dog}, #{Dog}, and #{DOG}.";
- Output:
The three dogs are named Benjamin, Samba, and Bernie.
Simula
Simula identifiers are case-insensitive, and the compiler will indignantly reject a program that tries to declare multiple variables with names differing only in case. (Same with key words: Case of a character in Simula code generally only matters in a simple string or a character constant.)
begin
text dog;
dog :- blanks( 8 );
dog := "Benjamin";
Dog := "Samba";
DOG := "Bernie";
outtext( "There is just one dog, named " );
outtext( dog );
outimage
end
- Output:
There is just one dog, named Bernie
Smalltalk
Smalltalk's symbols are case sensitive.
|dog Dog DOG|
dog := 'Benjamin'.
Dog := 'Samba'.
DOG := 'Bernie'.
( 'The three dogs are named %1, %2 and %3' %
{ dog . Dog . DOG } ) displayNl.
Outputs:
The three dogs are named Benjamin, Samba and Bernie
SNOBOL4
DOG = 'Benjamin'
Dog = 'Samba'
dog = 'Bernie'
OUTPUT = 'The three dogs are named ' DOG ', ' Dog ', and ' dog
END
- Output:
The three dogs are named Benjamin, Samba, and Bernie
Standard ML
Standard ML is case sensitive.
let
val dog = "Benjamin"
val Dog = "Samba"
val DOG = "Bernie"
in
print("The three dogs are named " ^ dog ^ ", " ^ Dog ^ ", and " ^ DOG ^ ".\n")
end;
- Output:
The three dogs are named Benjamin, Samba, and Bernie.
Stata
Stata is case-sensitive.
. local dog Benjamin
. local Dog Samba
. local DOG Bernie
. display "The three dogs are named $_dog, $_Dog, and $_DOG."
The three dogs are named Benjamin, Samba, and Bernie.
Swift
let dog = "Benjamin"
let Dog = "Samba"
let DOG = "Bernie"
println("The three dogs are named \(dog), \(Dog), and \(DOG).")
Tcl
Tcl variable names are case sensitive:
set dog "Benjamin"
set Dog "Samba"
set DOG "Bernie"
puts "The three dogs are named $dog, $Dog and $DOG"
Which prints...
The three dogs are named Benjamin, Samba and Bernie
True BASIC
True Basic is case-insensitive
LET dog$ = "Benjamin"
LET Dog$ = "Samba"
LET DOG$ = "Bernie"
PRINT "There is just one dog, named "; dog$
END
UNIX Shell
dog="Benjamin"
Dog="Samba"
DOG="Bernie"
echo "The three dogs are named $dog, $Dog and $DOG."
The three dogs are named Benjamin, Samba and Bernie.
Ursa
Ursa names are case sensitive:
> decl string dog Dog DOG
> set dog "Benjamin"
> set Dog "Samba"
> set DOG "Bernie"
> out "The three dogs are named " dog ", " Dog ", and " DOG endl console
The three dogs are named Benjamin, Samba, and Bernie
>
VBA
VBA is case sensitive case insensitive. The variable names 'dog', 'Dog' and 'DOG' can not co-exist.
Public Sub case_sensitivity()
'VBA does not allow variables that only differ in case
'The VBA IDE vbe will rename variable 'dog' to 'DOG'
'when trying to define a second variable 'DOG'
Dim DOG As String
DOG = "Benjamin"
DOG = "Samba"
DOG = "Bernie"
Debug.Print "There is just one dog named " & DOG
End Sub
- Output:
There is just one dog named Bernie
Wren
Identifiers in Wren are case sensitive.
var dog = "Benjamin"
var Dog = "Samba"
var DOG = "Bernie"
System.print("The three dogs are named %(dog), %(Dog) and %(DOG).")
- Output:
The three dogs are named Benjamin, Samba and Bernie.
XBS
In XBS variable names are case-sensitive.
set dog="Benjamin";
set DOG="Samba";
set Dog="Bernie";
log(`The three dogs are named {dog}, {DOG} and {Dog}.`);
- Output:
The three dogs are named Benjamin, Samba and Bernie.
XLISP
XLISP is entirely case-insensitive. The user can decide whether to have the system print symbols, etc., in capitals or in lower case, by assigning to the variable *PRINT-CASE*.
(SETQ DOG 'BENJAMIN)
(SETQ Dog 'SAMBA)
(SETQ dog 'BERNIE)
(DISPLAY `(THERE IS JUST ONE DOG NAMED ,DOG))
There is, in any event, only one dog.
(THERE IS JUST ONE DOG NAMED BERNIE)
XPL0
XPL0 is normally case-insensitive, so there is really just one dog named Bernie. However, it has a command-line switch (/c) that turns case sensitivity on. All names must start with a capital letter (or an underline, so they can't clash with command words such as 'for'). Thus "dog" cannot be used as a name, but Dog, DOG and DoG (and For) can. The intent of the command-line switch (/c) is to detect inconsistent capitalizing of names such as Ascii and ASCII or CpuReg and CPUReg.
Yabasic
Yabasic names are case sensitive:
dog$ = "Benjamin"
Dog$ = "Samba"
DOG$ = "Bernie"
print "The three dogs are named ", dog$, ", ", Dog$, " and ", DOG$
end
zkl
var dog = "Benjamin", Dog = "Samba", DOG = "Bernie";
- Output:
vars L(L("DOG","Bernie"),L("Dog","Samba"),L("dog","Benjamin"))
ZX Spectrum Basic
10 LET D$="Benjamin"
20 PRINT "There is just one dog named ";d$
- Programming Tasks
- Case Sensitivity
- 11l
- Action!
- Ada
- Agena
- Aime
- ALGOL 68
- ALGOL W
- APL
- Arturo
- AutoHotkey
- AWK
- BASIC
- BASIC256
- Batch File
- BBC BASIC
- Bc
- Bracmat
- Brlcad
- C
- C sharp
- C++
- Clojure
- COBOL
- CoffeeScript
- Common Lisp
- Crystal
- D
- Dc
- Delphi
- DWScript
- Déjà Vu
- EasyLang
- EchoLisp
- Ecstasy
- Elena
- Elixir
- Erlang
- Euphoria
- F Sharp
- Factor
- Forth
- Fortran
- FreeBASIC
- Frink
- FutureBasic
- Gambas
- GAP
- Go
- Groovy
- Haskell
- Icon
- Unicon
- J
- Java
- JavaScript
- Jq
- Julia
- K
- Kotlin
- Lasso
- Liberty BASIC
- Lua
- M2000 Interpreter
- Maple
- Mathematica
- Wolfram Language
- MATLAB
- Octave
- Maxima
- Min
- MiniScript
- Modula-2
- Nanoquery
- Nemerle
- NESL
- NetRexx
- Nim
- Oberon-2
- Objeck
- OCaml
- Oforth
- Ol
- PARI/GP
- Pascal
- Perl
- Phix
- Phix/basics
- PicoLisp
- PL/I
- Plain English
- PowerShell
- Prolog
- PureBasic
- Python
- Quackery
- R
- Racket
- Raku
- Retro
- REXX
- Ring
- Ruby
- Run BASIC
- Rust
- Sather
- Scala
- Scheme
- Seed7
- SenseTalk
- SETL
- Sidef
- Simula
- Smalltalk
- SNOBOL4
- Standard ML
- Stata
- Swift
- Tcl
- True BASIC
- UNIX Shell
- Ursa
- VBA
- Wren
- XBS
- XLISP
- XPL0
- Yabasic
- Zkl
- ZX Spectrum Basic
- 360 Assembly/Omit
- 6502 Assembly/Omit
- 8051 Assembly/Omit
- 8080 Assembly/Omit
- 8086 Assembly/Omit
- 68000 Assembly/Omit
- AArch64 Assembly/Omit
- ARM Assembly/Omit
- MIPS Assembly/Omit
- Sed/Omit
- X86 Assembly/Omit
- Z80 Assembly/Omit