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Module @swim/dataflow


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@swim/dataflow implements a compiler from @swim/structure selectors, operators, and functions, to continuously updated data structures driven by @swim/streamlet dataflow graphs. @swim/dataflow turns dynamic data structures into living documents. @swim/dataflow is written in TypeScript, but can be used from either TypeScript or JavaScript. @swim/dataflow is included as part of the @swim/core framework.


A live updated data structure is represented as a RecordScope, which extends Record from @swim/structure. An ordinary Record can be recursively compiled into a RecordScope by invoking the RecordScope.from factory method. A compiled RecordScope has all of its nested expressions replaced by their evaluated state. But unlike evaluating a Record with an Interpreter, if a member of a RecordScope changes, all expressions that transitively depend on that member get flagged for recomputation, which occurs the next time reconcileInput gets invoked on the RecordScope.

The Dataflow.compile method can also be used to compile an arbitrary @swim/structure expression into an Outlet that updates whenever the state of any of its transitively dependend expressions changes.



For an npm-managed project, npm install @swim/dataflow to make it a dependency. TypeScript sources will be installed into node_modules/@swim/dataflow/main. Transpiled JavaScript and TypeScript definition files install into node_modules/@swim/dataflow/lib/main. And a pre-built UMD script can be found in node_modules/@swim/dataflow/dist/main/swim-dataflow.js.


Web applications can load swim-core.js, which comes bundled with the @swim/dataflow library, directly from the Swim CDN.

<script src="https://cdn.swim.ai/js/latest/swim-core.js"></script>



@swim/dataflow can be imported as an ES6 module from TypeScript and other ES6-compatible environments.

import * as dataflow from "@swim/dataflow";


@swim/dataflow can also be used as a CommonJS in Node.js applications.

var dataflow = require("@swim/dataflow");


When loaded by a web browser, the swim-core.js script adds the @swim/dataflow library exports to the global swim namespace.