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#355 in Web programming

25 downloads per month
Used in 7 crates

MIT license



flowcore is a library of structs and traits related to flow that are shared between multiple crates in the flowproject.

Implementation trait

This is a trait that implementations of flow 'functions' must implement in order for them to be invoked by the flowrlib (or other) run-time library.

An example of a function implementing the Implementation trait can be found in docs.rs for Implementation


This implements a content provider that resolves URLs and then gets the content of the url.


flowcore crate supports a number of "features" for conditional compiling with more or less features.


These are the conditionally compiled features of flowcore:

  • default - none are activated by default
  • context - makes this crate aware of the flow context functions or not
  • debugger - feature to add the debugger
  • online_tests - run any tests activated by this feature
  • meta_provider - include the meta provider for resolving "lib://" and "context://" Urls
  • file_provider - include a provider to fetch content from the file system
  • http_provider - include a provider to fetch content from the web


  • flowrlib library crate compiles flowcore activating the "file_provider", "http_provider", "context" and "meta_provider" features
  • flowr compiled flowcore activating the "context" feature as it provides context functions. It has a number of features that, if activated, active corresponding features in flowcore (flowr "debugger" feature actives "flowcore/debugger" feature.) and it depends on flowrlib (above) that in turn activates features
  • flowrex compiles flowcore with the default set of features (which is the minimal set in the case of flowcore as it does not provide ant context functions ("context" feature), nor does it coordinate flow running and provide a debugger ("debugger" feature), nor does it have the need for running "online_tests", and lastly it does not fetch content via any of the various "providers" ("meta_provider", "file_provider", and "http_provider" features).


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