instance method String#scan

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String#scan(pattern, iterator) → String

Allows iterating over every occurrence of the given pattern (which can be a string or a regular expression). Returns the original string.

Internally just calls String#gsub passing it pattern and iterator as arguments.

'apple, pear & orange'.scan(/\w+/, alert);
// -> 'apple pear & orange' (and displays 'apple', 'pear' and 'orange' in three successive alert dialogs)

Can be used to populate an array:

var fruits = [];
'apple, pear & orange'.scan(/\w+/, function(match) { fruits.push(match[0]) });
// -> ['apple', 'pear', 'orange']

or even to work on the DOM:

'failure-message, success-message & spinner'.scan(/(\w|-)+/, Element.toggle)
// -> 'failure-message, success-message & spinner' (and toggles the visibility of each DOM element)

Do not use the "g" flag on the regex as this will create an infinite loop.