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108 lines
2.0 KiB
JavaScript
Executable File
108 lines
2.0 KiB
JavaScript
Executable File
/**********************************************************************
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*
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* JavaScript types and objects
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*
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*
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**********************************************************************/
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//
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// Types and objects
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// =================
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//
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// JavaScript's type system is split into two categories of enteties:
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// basic types or values and objects, they differ in several aspects.
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//
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// | values | objects
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// ----------------+-------------------+--------------------------
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// mutability | imutable | mutable
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// ----------------+-------------------+--------------------------
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// identity | equal values are | different objects
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// | the same entity | can have same
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// | (singletons) | structure
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// ----------------+-------------------+--------------------------
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//
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//
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// Basic values
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// ------------
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//
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// numbers
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var integer = 123
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var floating_point = 3.1415
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var hex = 0xFF
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// strings
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var string = 'string'
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var another_string = "also a string"
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var template = `
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a template string.
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this can include \\n's
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also summorts expansions ${ '.' }`
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// boolieans
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var t = true
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var f = false
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// nulls
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var n = null
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var u = undefined
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var not_a_number = NaN
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// Values are in general:
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//
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// - singletons
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var a = 3.14
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var b = 3.14
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a === b // -> true
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// In general equal basic values are the same value and there is
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// no way to create two copies of the same value.
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// - imutable
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var a = 1
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var b = a
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// a and b hold the same value (1)
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a === b // -> true
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// now we update a...
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a += 1
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a === b // -> false
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// Note that we updated the value referenced by a, i.e. the old
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// value (1) was not modified by the addition (b is still 1),
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// rather a new value (2) was created and assigned to a.
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// Equality and identity
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//
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// Type cecking
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//
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// Objects
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// -------
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//
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// Type cheking
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//
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// Prototypes and inheritance
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//
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//
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// Constructors
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//
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//
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/**********************************************************************
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* vim:set ts=4 sw=4 : */
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