The history of Promises

  • This person wrote a more than adequate and substantial commentary. Below is my summary and additions.

The Promise idea has its origins in an older

The 1997 E language is almost in the same form as Promise is today.

MochiKit, a lightweight JavaScript library, was implemented in 2005 with reference to Twisted

Dojo, Q, and a number of other JavaScript libraries began to adopt similar concepts, and jQuery did so in 2010.

  • Dojo Toolkit - Wikipedia
  • Q
  • jQuery was at least for a time a very major JavaScript librarynishio.icon
    • The air of someone who doesn’t know much about it and uses it anyway.
    • jQuery has allowed “this way of doing things” to spread to a wide range of JavaScript programmers.

A unified test case Promises/A+ was created, and the mixed implementations of “this way of doing things” became “Promise implementations that behave the same”.

  • This also helped standardization by objectively demonstrating that a single concept of “Promise” is used in a wide range

It was then standardized in 2015 in the form of ES2015.


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