JavaScript Objects built on arrrays [duplicate]
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This question already has an answer here:
Why can I add named properties to an array as if it were an object?
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Difference between array & object in js?
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associative array versus object in javascript
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From my readings, in JavaScript:
Objects = Hash Tables, which are build on Arrays. However, it is commonly said that Arrays are Objects in JS. How are these two concepts reconciled?
javascript arrays hash hashtable javascript-objects
asked Nov 19 at 11:06
MiddleZ
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marked as duplicate by Stuart, trincot arrays
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Nov 19 at 11:13
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
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This question already has an answer here:
Why can I add named properties to an array as if it were an object?
7 answers
Difference between array & object in js?
2 answers
associative array versus object in javascript
7 answers
From my readings, in JavaScript:
Objects = Hash Tables, which are build on Arrays. However, it is commonly said that Arrays are Objects in JS. How are these two concepts reconciled?
javascript arrays hash hashtable javascript-objects
asked Nov 19 at 11:06
MiddleZ
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marked as duplicate by Stuart, trincot arrays
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Nov 19 at 11:13
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
A 10 second google gives: eloquentjavascript.net/04_data.html, and metaltoad.com/blog/…
– Stuart
Nov 19 at 11:09
4
Objects are not built on arrays - it's the other way around.
– CertainPerformance
Nov 19 at 11:09
Maybe you mean this:typeof ; //returns objector thisnew String()I would rather say everything in JS is build on objects.
– Zydnar
Nov 19 at 11:17
myArr = ['this', 'is', 'an', 'array']is actually{ 0: 'this', 1: 'is', 2: 'an', 3: 'array' }behind the scenes.
– AnonymousSB
Nov 19 at 11:23
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up vote
-1
down vote
favorite
up vote
-1
down vote
favorite
This question already has an answer here:
Why can I add named properties to an array as if it were an object?
7 answers
Difference between array & object in js?
2 answers
associative array versus object in javascript
7 answers
From my readings, in JavaScript:
Objects = Hash Tables, which are build on Arrays. However, it is commonly said that Arrays are Objects in JS. How are these two concepts reconciled?
javascript arrays hash hashtable javascript-objects
asked Nov 19 at 11:06
MiddleZ
316
This question already has an answer here:
Why can I add named properties to an array as if it were an object?
7 answers
Difference between array & object in js?
2 answers
associative array versus object in javascript
7 answers
From my readings, in JavaScript:
Objects = Hash Tables, which are build on Arrays. However, it is commonly said that Arrays are Objects in JS. How are these two concepts reconciled?
This question already has an answer here:
Why can I add named properties to an array as if it were an object?
7 answers
Difference between array & object in js?
2 answers
associative array versus object in javascript
7 answers
javascript arrays hash hashtable javascript-objects
javascript arrays hash hashtable javascript-objects
asked Nov 19 at 11:06
MiddleZ
316
asked Nov 19 at 11:06
MiddleZ
316
asked Nov 19 at 11:06
MiddleZ
316
asked Nov 19 at 11:06
MiddleZ
316
asked Nov 19 at 11:06
MiddleZ
316
316
marked as duplicate by Stuart, trincot arrays
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Nov 19 at 11:13
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Nov 19 at 11:13
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
A 10 second google gives: eloquentjavascript.net/04_data.html, and metaltoad.com/blog/…
– Stuart
Nov 19 at 11:09
4
Objects are not built on arrays - it's the other way around.
– CertainPerformance
Nov 19 at 11:09
Maybe you mean this:typeof ; //returns objector thisnew String()I would rather say everything in JS is build on objects.
– Zydnar
Nov 19 at 11:17
myArr = ['this', 'is', 'an', 'array']is actually{ 0: 'this', 1: 'is', 2: 'an', 3: 'array' }behind the scenes.
– AnonymousSB
Nov 19 at 11:23
add a comment |
A 10 second google gives: eloquentjavascript.net/04_data.html, and metaltoad.com/blog/…
– Stuart
Nov 19 at 11:09
4
Objects are not built on arrays - it's the other way around.
– CertainPerformance
Nov 19 at 11:09
Maybe you mean this:typeof ; //returns objector thisnew String()I would rather say everything in JS is build on objects.
– Zydnar
Nov 19 at 11:17
myArr = ['this', 'is', 'an', 'array']is actually{ 0: 'this', 1: 'is', 2: 'an', 3: 'array' }behind the scenes.
– AnonymousSB
Nov 19 at 11:23
A 10 second google gives: eloquentjavascript.net/04_data.html, and metaltoad.com/blog/…
– Stuart
Nov 19 at 11:09
A 10 second google gives: eloquentjavascript.net/04_data.html, and metaltoad.com/blog/…
– Stuart
Nov 19 at 11:09
4
4
Objects are not built on arrays - it's the other way around.
– CertainPerformance
Nov 19 at 11:09
Objects are not built on arrays - it's the other way around.
– CertainPerformance
Nov 19 at 11:09
Maybe you mean this:
typeof ; //returns object or this new String() I would rather say everything in JS is build on objects.– Zydnar
Nov 19 at 11:17
Maybe you mean this:
typeof ; //returns object or this new String() I would rather say everything in JS is build on objects.– Zydnar
Nov 19 at 11:17
myArr = ['this', 'is', 'an', 'array'] is actually { 0: 'this', 1: 'is', 2: 'an', 3: 'array' } behind the scenes.– AnonymousSB
Nov 19 at 11:23
myArr = ['this', 'is', 'an', 'array'] is actually { 0: 'this', 1: 'is', 2: 'an', 3: 'array' } behind the scenes.– AnonymousSB
Nov 19 at 11:23
add a comment |
1 Answer
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Objects are not built on arrays. Objects have their own optimizations.
In general:
- Objects are for "structs", structures of predictable "shape" and keys known in advance (even though they can be used with dynamic keys, you should use Maps for that. See below).
- Arrays are for lists (and queues, and stacks), structures where the keys are numbers, or where the order of elements matters. Arrays are "special" objects, not the other way around. (You can put string-based properties on an array, just like any object. Please don't do that though).
Maps are for hash tables/dictionaries, structures where the keys are dynamic and not known in advance.
add a comment |
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
Objects are not built on arrays. Objects have their own optimizations.
In general:
- Objects are for "structs", structures of predictable "shape" and keys known in advance (even though they can be used with dynamic keys, you should use Maps for that. See below).
- Arrays are for lists (and queues, and stacks), structures where the keys are numbers, or where the order of elements matters. Arrays are "special" objects, not the other way around. (You can put string-based properties on an array, just like any object. Please don't do that though).
Maps are for hash tables/dictionaries, structures where the keys are dynamic and not known in advance.
add a comment |
up vote
0
down vote
Objects are not built on arrays. Objects have their own optimizations.
In general:
- Objects are for "structs", structures of predictable "shape" and keys known in advance (even though they can be used with dynamic keys, you should use Maps for that. See below).
- Arrays are for lists (and queues, and stacks), structures where the keys are numbers, or where the order of elements matters. Arrays are "special" objects, not the other way around. (You can put string-based properties on an array, just like any object. Please don't do that though).
Maps are for hash tables/dictionaries, structures where the keys are dynamic and not known in advance.
add a comment |
up vote
0
down vote
up vote
0
down vote
Objects are not built on arrays. Objects have their own optimizations.
In general:
- Objects are for "structs", structures of predictable "shape" and keys known in advance (even though they can be used with dynamic keys, you should use Maps for that. See below).
- Arrays are for lists (and queues, and stacks), structures where the keys are numbers, or where the order of elements matters. Arrays are "special" objects, not the other way around. (You can put string-based properties on an array, just like any object. Please don't do that though).
Maps are for hash tables/dictionaries, structures where the keys are dynamic and not known in advance.
Objects are not built on arrays. Objects have their own optimizations.
In general:
- Objects are for "structs", structures of predictable "shape" and keys known in advance (even though they can be used with dynamic keys, you should use Maps for that. See below).
- Arrays are for lists (and queues, and stacks), structures where the keys are numbers, or where the order of elements matters. Arrays are "special" objects, not the other way around. (You can put string-based properties on an array, just like any object. Please don't do that though).
Maps are for hash tables/dictionaries, structures where the keys are dynamic and not known in advance.
answered Nov 19 at 11:10
community wiki
Madara Uchiha
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add a comment |
A 10 second google gives: eloquentjavascript.net/04_data.html, and metaltoad.com/blog/…
– Stuart
Nov 19 at 11:09
4
Objects are not built on arrays - it's the other way around.
– CertainPerformance
Nov 19 at 11:09
Maybe you mean this:
typeof ; //returns objector thisnew String()I would rather say everything in JS is build on objects.– Zydnar
Nov 19 at 11:17
myArr = ['this', 'is', 'an', 'array']is actually{ 0: 'this', 1: 'is', 2: 'an', 3: 'array' }behind the scenes.– AnonymousSB
Nov 19 at 11:23