number-ranger

Interpret ranges from strings and use them easily.

Install

Install via npm:

npm install number-ranger

API

ranger.parse(s)

Parses and transforms a string into a easily usable range.

var ranger = require('number-ranger');

ranger.parse('2');
// --> [{ start: 2 }]

// Add ':' to make a range between two numbers
ranger.parse('2:3');
// --> [{ start: 2, end: 3 }]

// Create multiple ranges by separating them by ','
ranger.parse('2:3,4');
// --> [{ start: 2, end: 3 }, { start: 4 }]

// Floating numbers are fine
ranger.parse('.002:.4');
// --> [{ start: .002, end: .4 }]

// -/+ infinity is represented by $
ranger.parse('2:$');
// --> [{ start: 2, end: +Infinity }]
ranger.parse('$:2');
// --> [{ start: -Infinity, end: 2 }]

// Exclude bounds by prepending by x
ranger.parse('x2:4');
// --> [{ start: 2, end: 4, startIncluded: false }]
ranger.parse('2:x4');
// --> [{ start: 2, end: 4, endIncluded: false }]

You can specify your own symbols if you want. If you use forbidden symbols or have multiple keys have the same value, any calls will return false. If you wish to use odd and/or unforeseen symbols, test carefully beforehand to make sure it works. If you use symbols like '.', '-', you may lose the ability to parse floating or negative numbers for instance.

ranger.parse('2p}4?-47p%', {
    // All of these are optional. Only specify those you wish to override
    range: 'p',
    separator: '?',
    infinity: '%',
    exclude: '}'
});
// --> [
//     { start: 2, end: 4, endIncluded: false },
//     { start: -47, end: +Infinity }
// ]

ranger.parse('3', {
    range: '', // no empty strings
    separator: '   p', // no spaces,
    infinity: 'x' // not a conflicting symbol (= exclude's default symbol)
});
// --> false

ranger.isInRange(item, ranges[, key])

Checks if item is in the given ranges. Ranges can be a string as given for #ranger.parse(s), or the result of it. A key can also be provided when item is not a number but an object, and the value of item[key] will then be compared.

var ranger = require('number-ranger');

// Pass the result of ranger.range
ranger.isInRange(325, ranger.parse('300:350'));
// --> true

// or ranger.ranger will be used implicitly
ranger.isInRange(450, '400:450');
// --> true

ranger.isInRange(0, '400:450');
// --> false

ranger.isInRange(450, [{
    start: 400,
    end: 500
}]);
// --> true

// By specifying a field, it will consider item to be an object and use item[key] as the value
ranger.isInRange({ value: 450 }, '400:450', 'value');
// --> true

// The order of start and end are not important
ranger.isInRange(450, [{
    start: 500,
    end: 400
}]);
// --> true

// You can exclude bounds
ranger.isInRange(2, [{
    start: 2,
    end: 5,
    startIncluded: false
}]);
// --> false

ranger.isInRangeFilter(ranges[, key])

Returns an easy filter function that removes items that wouldn't match ranger.isInRange(item, ranges). Ranges can be a string as given for #ranger.parse(s), or the result of it. A key can also be provided when item is not a number but an object, and the value of item[key] will then be compared.

var ranger = require('number-ranger');

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10].filter(ranger.isInRangeFilter([{
    start: 0,
    end: 5
}]));
// --> [0, 1, 2, 3, 4, 5]

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10].filter(ranger.isInRangeFilter('0:4'));
// --> [0, 1, 2, 3, 4]

[{ value: 0 }, { value: 1 }, { value: 2 }, { value: 3 }, { value: 4 }].filter(ranger.isInRangeFilter('1:3', 'value'));
// --> [{ value: 1 }, { value: 2 }, { value: 3 }]