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The FAQ doesn't mention anything about this -- can you explain how Seaside uses continuations?

by long 11y ago

doublec 11y ago
It uses continuations to hide the asynchronous nature of web requests and allows the flow between pages of a web app to be written in an imperative style. "Inverting back the inversion of control" describes the idea (in Scheme) https://pages.lip6.fr/Christian.Queinnec/PDF/www.pdf https://pages.lip6.fr/Christian.Queinnec/PDF/www.pdf Paul Graham used the idea in ViaWeb - and apparently got a patent on some aspect of it https://web.archive.org/web/20060323211251/http://paulgraham.infogami.com/blog/morepatents https://web.archive.org/web/20060323211251/http://paulgraham...
- agumonkey 11y ago
  IIUC HN uses them too.
- mbrock 11y ago
  There are a couple of continuation-based web frameworks for Ruby (Borges, Wee), but they're old and abandoned as far as I know. I suspect it didn't catch on because (1) people are afraid of continuations, and (2) web apps are typically designed in at least a pseudo-REST-like style, so the paradigm of "asking" the user (like "await" in ES6) isn't needed very often. But it's a cool thing to be able to do, especially for funnel-type flows, and other types of more complex session-based interactions. I wonder if there are any JavaScript inversion of control things for client side code. I've been working for the past week on a signup funnel with React and Flux, and it's just a big explicit state machine... which kind of works, but is also kind of tedious.
  - doublec 11y ago
    I think 'Ajax' killed continuation based web servers. See Avi Bryant's thoughts in this area from back then: https://web.archive.org/web/20060610180033/http://smallthought.com/avi/?p=14 https://web.archive.org/web/20060610180033/http://smallthoug... There were client side JavaScript continuation like things. Back in the mid-2000's there was Narrative JavaScript. I used it to implement threads and Alice ML style futures/promises on the client side: https://bluishcoder.co.nz/2006/06/05/more-concurrency-in-narrative.html https://bluishcoder.co.nz/2006/06/05/more-concurrency-in-nar...
  - klibertp 11y ago
    There's also Nagare in Python: http://www.nagare.org/trac/wiki/NagareTutorial http://www.nagare.org/trac/wiki/NagareTutorial IIRC it uses Stackless Python, not the standard interpreter, and I don't know how active its development is.

The FAQ doesn't mention anything about this -- can you explain how Seaside uses continuations?

by long 11y ago

The FAQ doesn't mention anything about this -- can you explain how Seaside uses continuations?

It uses continuations to hide the asynchronous nature of web requests and allows the flow between pages of a web app to be written in an imperative style. "Inverting back the inversion of control" describes the idea (in Scheme) https://pages.lip6.fr/Christian.Queinnec/PDF/www.pdf https://pages.lip6.fr/Christian.Queinnec/PDF/www.pdf Paul Graham used the idea in ViaWeb - and apparently got a patent on some aspect of it https://web.archive.org/web/20060323211251/http://paulgraham.infogami.com/blog/morepatents https://web.archive.org/web/20060323211251/http://paulgraham...

agumonkey 11y ago
IIUC HN uses them too.
mbrock 11y ago
There are a couple of continuation-based web frameworks for Ruby (Borges, Wee), but they're old and abandoned as far as I know. I suspect it didn't catch on because (1) people are afraid of continuations, and (2) web apps are typically designed in at least a pseudo-REST-like style, so the paradigm of "asking" the user (like "await" in ES6) isn't needed very often. But it's a cool thing to be able to do, especially for funnel-type flows, and other types of more complex session-based interactions. I wonder if there are any JavaScript inversion of control things for client side code. I've been working for the past week on a signup funnel with React and Flux, and it's just a big explicit state machine... which kind of works, but is also kind of tedious.
- doublec 11y ago
  I think 'Ajax' killed continuation based web servers. See Avi Bryant's thoughts in this area from back then: https://web.archive.org/web/20060610180033/http://smallthought.com/avi/?p=14 https://web.archive.org/web/20060610180033/http://smallthoug... There were client side JavaScript continuation like things. Back in the mid-2000's there was Narrative JavaScript. I used it to implement threads and Alice ML style futures/promises on the client side: https://bluishcoder.co.nz/2006/06/05/more-concurrency-in-narrative.html https://bluishcoder.co.nz/2006/06/05/more-concurrency-in-nar...
- klibertp 11y ago
  There's also Nagare in Python: http://www.nagare.org/trac/wiki/NagareTutorial http://www.nagare.org/trac/wiki/NagareTutorial IIRC it uses Stackless Python, not the standard interpreter, and I don't know how active its development is.