Simon Willison’s Weblog

How is a dictionary (key value) related to a hash?

2nd September 2013

My answer to How is a dictionary (key value) related to a hash? on Quora

The following terms describe essentially the same data structure across a number of different languages:

A Perl hash
A Ruby hash
A Python dictionary
A Java Map (an interface used by HashMap and others)
A Lua table
A JavaScript object (if you ignore object prototypes)

Posted 2nd September 2013 at 4:32 pm · Follow me on Mastodon, Bluesky, Twitter or subscribe to my newsletter

More recent articles

Introducing Showboat and Rodney, so agents can demo what they’ve built - 10th February 2026
How StrongDM's AI team build serious software without even looking at the code - 7th February 2026
Running Pydantic's Monty Rust sandboxed Python subset in WebAssembly - 6th February 2026

This is How is a dictionary (key value) related to a hash? by Simon Willison, posted on 2nd September 2013.

programming 157 quora 1005

Next: What are good ways to rewrite a social network and still keep old users?

Previous: How do I quit the startup I founded without causing too much fallout?

Monthly briefing

Sponsor me for $10/month and get a curated email digest of the month's most important LLM developments.

Pay me to send you less!

Sponsor & subscribe