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David Novák
5,877 PointsWhy is it called dictionary instead of map?
Why is key - value date structure called dictionary and not map like in other programming languages?
1 Answer
Geoff Parsons
11,679 PointsJust quirks of languages. Python and Swift both call associative arrays dictionaries, Java tends towards Map, and javascript just refers to it as an associative array. If there are nuanced differences between these I'm not aware of them and in fact that wikipedia article on associative arrays seems to suggest it's all just naming preference as well:
In Smalltalk, Objective-C, .NET, Python, REALbasic, and Swift they are called dictionaries; in Perl, Ruby and Seed7 they are called hashes; in C++, Java, Go, Clojure, Scala, OCaml, Haskell they are called maps (see map (C++), unordered_map (C++), and Map); in Common Lisp and Windows PowerShell, they are called hash tables (since both typically use this implementation). In PHP, all arrays can be associative, except that the keys are limited to integers and strings. In JavaScript (see also JSON), all objects behave as associative arrays. In Lua, they are called tables, and are used as the primitive building block for all data structures. In Visual FoxPro, they are called Collections. The D language also has support for associative arrays.