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Re: plists, alists, and hashtables
From: |
Rusi |
Subject: |
Re: plists, alists, and hashtables |
Date: |
Fri, 7 Aug 2015 09:33:46 -0700 (PDT) |
User-agent: |
G2/1.0 |
On Friday, August 7, 2015 at 12:50:20 AM UTC+5:30, Stefan Monnier wrote:
> > In short a map is the fundamental data structure.¹
>
> Beware: there are maps and then there are maps.
> E.g. Javascript's objects are maps (typically thought of as being
> implemented as some kind of hash-tables), yet Javascript also comes with
> hash-tables.
Thats the whole point
Python: Zen on python makes a big todo about namespaces because they work
uniformly and nicely for objects, classes, modules... All of which are
dictionaries ie maps
Lua: Only one collection data structure -- the table.
Tables made without explicit keys just use 1,2,3 etc ie normal lists with
the expected convenient lists syntax. Brings me to...
SQL: All of sql hangs around relations. May be called 'relation' but they
are invariably key → tuple maps
Finally a more 'fundamentalist' viewpoint:
Programmers write functions as their most primary activity
If they are algorithmic they are the functions that all programmers daily use
If they are just looked-up they are 'data-maps' -- for which a hash-table is
a typical² data structure
IOW functions-as-code and functions-as-data are a primary dual
-----------
¹ No attribution line...Assuming you are quoting me....
² If 90% of all maps/associations are smaller than 10-15, then a linear lookup
would be clearly a win over more fancy (Pascal's point I think). My point is
more that the *idea* of a map needs to be fundamental not the details of
*implementation*
- plists, alists, and hashtables (was: How to iterate over properties in a plist?), Ted Zlatanov, 2015/08/04
- Re: plists, alists, and hashtables (was: How to iterate over properties in a plist?), Rusi, 2015/08/05
- Re: plists, alists, and hashtables, Pascal J. Bourguignon, 2015/08/05
- Re: plists, alists, and hashtables, Ted Zlatanov, 2015/08/05
- Re: plists, alists, and hashtables, Rusi, 2015/08/05
- Re: plists, alists, and hashtables, Stefan Monnier, 2015/08/06
- Message not available
- Re: plists, alists, and hashtables,
Rusi <=
- Re: plists, alists, and hashtables, Pascal J. Bourguignon, 2015/08/05
- Re: plists, alists, and hashtables, Ted Zlatanov, 2015/08/05
- Re: plists, alists, and hashtables, Barry Margolin, 2015/08/05
- Re: plists, alists, and hashtables, Robert Thorpe, 2015/08/05
- Re: plists, alists, and hashtables, Pascal J. Bourguignon, 2015/08/05
- Re: plists, alists, and hashtables, Ted Zlatanov, 2015/08/06
- Re: plists, alists, and hashtables, Pascal J. Bourguignon, 2015/08/06
- RE: plists, alists, and hashtables, Drew Adams, 2015/08/06
- Re: plists, alists, and hashtables, Ted Zlatanov, 2015/08/06
- Re: plists, alists, and hashtables, Pascal J. Bourguignon, 2015/08/06