Computer Science Canada :: View topic - Syntax Quickref: Turing <--> Eiffel

Computer Science Canada

Syntax Quickref: Turing <--> Eiffel

Author:

wtd [ Wed Mar 16, 2005 5:03 pm ]

Post subject:

Syntax Quickref: Turing <--> Eiffel

Eiffel for the Turing Programmer

Input-Output

Printing to the standard output.

Turing

code:

put "Hello"

Eiffel

code:

std_output.put_string("Hello")
std_output.put_new_line

The same, without skipping to a newline.

Turing

code:

put "Hello" ..

Eiffel

code:

std_output.put_string("Hello")

Printing an integer.

Turing

code:

put 42

Eiffel

code:

std_output.put_integer(42)
std_output.put_new_line

Printing a floating point number.

Turing

code:

put 42.3

Eiffel

code:

std_output.put_real(42.3)
std_output.put_new_line

Getting a line from the keyboard.

Turing

code:

var line : string
get line : *

Eiffel

code:

test_proc is
local
line : STRING
do
std_input.read_line
line := std_input.last_string
end

Getting a single character from the keyboard.

Turing

code:

var ch : string
get ch : 1

Eiffel

code:

test_proc is
local
ch : CHARACTER
do
std_input.read_character
ch := std_input.last_character
end

Getting an integer from the keyboard.

Turing

code:

var i : int
get i

Eiffel

code:

test_proc is
local
i : INTEGER
do
std_input.read_integer
i := std_input.last_integer
end

Getting a float from the keyboard.

Turing

code:

var f : real
get f

Eiffel

code:

test_proc is
local
f : REAL
do
std_input.read_real
f := std_input.last_real
end

Math

code:

Turing | Eiffel | Result
----------+--------------+---------
4 + 3 | 4 + 3 | 7
4 - 2 | 4 - 2 | 2
2 * 3 | 2 * 3 | 6
2 / 5 | 2 / 5 | 0.4
6 div 4 | | 1
6 rem 4 | 6 \\ 4 | 2
3 ** 2 | 3 ^ 2 | 9.0
sin | sine |
cos | cosine |
| tangent |
| arc_sine |
| arc_cosine |
| arc_tangent |

Comparisons

code:

Turing | Eiffel
--------+----------
= | =
not= | /=
<, <= | <, <=
>, >= | >, >=
not | not
and | and/and then
or | or/or else

Conditional Statements/Expressions

code:

Turing | Eiffel
----------------------------+------------------------------
if condition then | if condition then
statement1 | statement1
elsif otherCondition then | elsif otherCondition then
statement2 | statement2
else | else
defaultStatement | defaultStatement
end if | end
----------------------------+------------------------------
case value of | inspect value
label 1: statement1 | when 1 then statement1
label 2: statement2 | when 2 then statement2
label: default | else default
end case | end

Function Definition

code:

Turing | Eiffel
------------------------------------+--------------------------------------------
function fooBar : string | foo_bar : STRING is
result "foo, bar" | do
end fooBar | Result := "foo, bar"
| end
------------------------------------+--------------------------------------------
function square (n : int) : float | square(n : INTEGER) : REAL is
result n ** 2 | do
end square | Result := n ^ 2
| end
------------------------------------+--------------------------------------------
procedure greet (name : string) | greet(name : STRING) is
put "Hello, " + name | do
end greet | std_input.put_string("Hello, " + name)
| std_input.put_new_line
| end
------------------------------------+--------------------------------------------
procedure greet (name : string) | greet(name : STRING) is
var greeting := "Hello, " + name | local
put greeting | greeting : STRING
end greet | do
| greeting := "Hello, " + name
| std_input.put_string("Hello, " + name)
| std_input.put_new_line
| end
------------------------------------+--------------------------------------------
function fact (n : int) : int | fact(n : INTEGER) : INTEGER is
if n = 0 then | do
result 1 | if n = 0 then
else | Result := 1
result n * fact (n - 1) | else
end if | Result := n * fact(n - 1)
end fact | end
| end

Comments

code:

Turing | Eiffel
------------+-------------
% | --
/* ... */ |

More to come.

:

You can syndicate this boards posts using the file backend.php or view the topic map using sitemap.php.

Terms of Use | Privacy Policy