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[paulkokos]

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[Mitsakos46]

PHP OPERATORS 1.Arithmetic operators 2.Assignment operators 3.Comparison operators 4.Logical operators 5.String operators 6.Array operators

1.Operator	Name	Example	Result
+	Addition	$x + $y	Sum of $x and $y
-	Subtraction	$x - $y	Difference of $x and $y
*	Multiplication	$x * $y	Product of $x and $y
/	Division	$x / $y	Quotient of $x and $y
%	Modulus	$x % $y	Remainder of $x divided by $y

2.Assignment	Same as...	Description
x = y	x = y	The left operand gets set to the value of the expression on the right
x += y	x = x + y	Addition
x -= y	x = x - y	Subtraction
x *= y	x = x * y	Multiplication
x /= y	x = x / y	Division
x %= y	x = x % y	Modulus

3.Operator	Name	Example	Result
==	Equal	$x == $y	Returns true if $x is equal to $y
===	Identical	$x === $y	Returns true if $x is equal to $y, and they are of the same type
!=	Not equal	$x != $y	Returns true if $x is not equal to $y
<>	Not equal	$x <> $y	Returns true if $x is not equal to $y
!==	Not identical	$x !== $y	Returns true if $x is not equal to $y, or they are not of the same type
>	Greater than	$x > $y	Returns true if $x is greater than $y
<	Less than	$x < $y	Returns true if $x is less than $y
>=	Greater than or equal to	$x >= $y	Returns true if $x is greater than or equal to $y
<=	Less than or equal to	$x <= $y	Returns true if $x is less than or equal to $y

4.Operator	Name	Example	Result
and	And	$x and $y	True if both $x and $y are true
or	Or	$x or $y	True if either $x or $y is true
xor	Xor	$x xor $y	True if either $x or $y is true, but not both
&&	And	$x && $y	True if both $x and $y are true
||	Or	$x || $y	True if either $x or $y is true
!	Not	!$x	True if $x is not true

5.Operator	Name	Example	Result
.	Concatenation	$txt1 . $txt2	Concatenation of $txt1 and $txt2
.=	Concatenation assignment	$txt1 .= $txt2	Appends $txt2 to $txt1

6.Operator	Name	Example	Result
+	Union	$x + $y	Union of $x and $y
==	Equality	$x == $y	Returns true if $x and $y have the same key/value pairs
===	Identity	$x === $y	Returns true if $x and $y have the same key/value pairs in the same order and of the same types
!=	Inequality	$x != $y	Returns true if $x is not equal to $y
<>	Inequality	$x <> $y	Returns true if $x is not equal to $y
!==	Non-identity	$x !== $y	Returns true if $x is not identical to $y

[Mitsakos46]

%option noyywrap %{

define Addition 100

define Subtraction 101

define Multiplication 102

define Division 103

define Modulus 104

define Equal 200

define Not_equal 201

define Greater_than 202

define Less_than 203

define Greater_than_or_equal_to 204

define Less_than_or_equal_to 205

define goal 300

include

include

%}

int attr; ws [\n\t]+ nzdigit [1-9] digit (0|{nzdigit}) letter [A-Za-z] id {letter}({letter}|{digit})*

%%

{ws} {/ do nothing /} "+" {attr=Addition;return(goal);} "-" {attr=Subtraction;return(goal);} "*" {attr=Multiplication;return(goal);} "/" {attr=Division;return(goal);} "%" {attr=Modulus;return(goal);} "==" {attr=Equal;return(goal);} "!=" {attr=Not_equal;return(goal);} ">" {attr=Greater_than;return(goal);} "<" {attr=Less_than;return(goal);} ">=" {attr=Greater_than_or_equal_to;return(goal);} "<=" {attr=Less_than_or_equal_to;return(goal);}

%%

int main() { int token; while ((token=yylex()) !=0) printf("%s <%d, %d> \n", yytext, token,attr); }