pair

class pair#( type T1 = int,
type T2 = T1 )

Provides a pair that carries two values, which can be different types.

Parameters

T1	optional The type of the first value of a pair. The default is int.
T2	optional The type of the second value of a pair. The default is the same type as T1.

Summary

pair	Provides a pair that carries two values, which can be different types.
Types
this_type	The shorthand of pair#(T1,T2).
Properties
first	The first value inside the pair.
second	The second value inside the pair.
Functions
new	Creates a pair of values of types T1 and T2.
eq	Returns 1 if this object is equal to the specified pair.
ne	Returns 1 if this object is not equal to the specified pair.
lt	Returns 1 if this object is less than the specified pair.
gt	Returns 1 if this object is greater than the specified pair.
le	Returns 1 if this object is less than or equal to the specified pair.
ge	Returns 1 if this object is greater than or equal to the specified pair.
clone	Creates a pair by cloning this object.
swap	Swaps the contents of this pair with the ones of the specified pair.

Types

this_type

typedef pair#( T1,
T2 ) this_type

The shorthand of pair#(T1,T2).

Properties

first

T1 first

The first value inside the pair.

Example

pair#(int, string) p = new( 1, "apple" );
assert( p.first == 1 );

second

T2 second

The second value inside the pair.

Example

pair#(int, string) p = new( 1, "apple" );
assert( p.second == "apple" );

Functions

new

function new( T1 first,
T2 second,
comparator#(this_type) cmp = null )

Creates a pair of values of types T1 and T2.

Arguments

first	The first value of a pair.
second	The second value of a pair.
cmp	optional A strategy object used to compare two pairs. If not specified or null, pair_comparator #(this_type) is used. The default is null.

Returns

None.

Example

pair#(int, string) p = new( 1, "apple" );

eq

function bit eq( const ref this_type p )

Returns 1 if this object is equal to the specified pair. The comparison is done by the strategy object specified at the object construction.

Argument

p	A pair to compare with.

Returns

If this object is equal to p, then returns 1. Otherwise, returns 0.

Example

pair#(int, string) p = new( 1, "apple" );
pair#(int, string) q = new( 1, "apple" );
assert( p.eq( q ) == 1 ); // 1 == 1 && "apple" == "apple"

ne

function bit ne( const ref this_type p )

Returns 1 if this object is not equal to the specified pair. The comparison is done by the strategy object specified at the object construction.

Argument

p	A pair to compare with.

Returns

If this object is not equal to p, then returns 1. Otherwise, returns 0.

Example

pair#(int, string) p = new( 1, "apple" );
pair#(int, string) q = new( 1, "orange" );
assert( p.ne( q ) == 1 ); // "apple" != "orange"

lt

function bit lt( const ref this_type p )

Returns 1 if this object is less than the specified pair. The comparison is done by the strategy object specified at the object construction.

Argument

p	A pair to compare with.

Returns

If this object is less than p, then returns 1. Otherwise, returns 0.

Example

pair#(int, string) p = new( 1, "apple" );
pair#(int, string) q = new( 2, "apple" );
assert( p.lt( q ) == 1 ); // 1 < 2

gt

function bit gt( const ref this_type p )

Returns 1 if this object is greater than the specified pair. The comparison is done by the strategy object specified at the object construction.

Argument

p	A pair to compare with.

Returns

If this object is greater than p, then returns 1. Otherwise, returns 0.

Example

pair#(int, string) p = new( 1, "orange" );
pair#(int, string) q = new( 1, "apple" );
assert( p.gt( q ) == 1 ); // "orange" > "apple" by the lexicographical order

le

function bit le( const ref this_type p )

Returns 1 if this object is less than or equal to the specified pair. The comparison is done by the strategy object specified at the object construction.

Argument

p	A pair to compare with.

Returns

If this object is less than or equal to p, then returns 1. Otherwise, returns 0.

Example

pair#(int, string) p = new( 1, "apple" );
pair#(int, string) q = new( 1, "orange" );
assert( p.le( q ) == 1 ); // "apple" < "orange" by the lexicographical order

ge

function bit ge( const ref this_type p )

Returns 1 if this object is greater than or equal to the specified pair. The comparison is done by the strategy object specified at the object construction.

Argument

p	A pair to compare with.

Returns

If this object is greater than or equal to p, then returns 1. Otherwise, returns 0.

Example

pair#(int, string) p = new( 2, "apple" );
pair#(int, string) q = new( 1, "orange" );
assert( p.ge( q ) == 1 ); // 2 > 1

clone

function this_type clone()

Creates a pair by cloning this object.

Returns

A cloned pair.

Example

pair#(int, string) p = new( 1, "apple" );
pair#(int, string) q = p.clone();
assert( p.eq( q ) == 1 );

swap

function void swap( ref this_type p )

Swaps the contents of this pair with the ones of the specified pair.

Argument

p	A pair to swap the contents.

Example

pair#(int, string) p = new( 1, "apple" );
pair#(int, string) q = new( 2, "orange" );
p.swap( q );
assert( p.first == 2 );
assert( q.first == 1 );
assert( p.second == "orange" );
assert( q.second == "apple" );