rsc3/doc-schelp/HelpSource/Reference/matchItem.schelp

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2022-08-24 13:53:18 +00:00
title::matchItem
categories::Common methods
summary::test if object fulfils a constraint
Implemented by: link::Classes/Object::, link::Classes/Collection::, link::Classes/Nil::, link::Classes/Function::
method:: matchItem(item)
matchItem(item) may be passed to different objects that behave as constraints. More Objects may be conceived to implement matchItem to extend the interface.
See also: link::Classes/Dictionary#-matchAt::.
section:: Object-matchItem
Test if strong::item:: is identical to strong::object::.
code::
a = [1, 2, 3, "wort", "1", [pi, 2pi]];
a.any { |x| x.matchItem(3) }; // true
a.any { |x| x.matchItem(5) }; // false
a.any { |x| x.matchItem("wort") }; // false, because "wort" == "wort" but not identical.
::
section::Collection-matchItem
Test if strong::item:: is included in strong::collection::.
code::
a = [1, 2, 3, "wort", "1", [pi, 2pi]];
a.any { |x| x.matchItem(pi) }; // true
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section::Nil-matchItem
returns true (link::Classes/Nil:: serves as a "joker", a stand-in for anything).
code::
a = [nil, 1, 2, 3, "wort", "1", [pi, 2pi]];
a.any { |x| x.matchItem(10000.rand) }; // true always
::
section::Function-matchItem
Test strong::item:: by passing it to a function which should return a link::Classes/Boolean::.
code::
a = [10, 20, 30, { |item| item.isPrime }];
a.any { |x| x.matchItem(3) }; // true
a.any { |x| x.matchItem(4) }; // false
a.any { |x| x.matchItem(10) }; // true
::