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constraint-list-builder v1.0.16

Used to build a list of nodes, each node defines it's constraints in a configuration file. The list of nodes has to be built using the configuration file.

Constraint List Builder

This project allows you to build a list but based on constraints that you set up.

You provide a defintion file when you initialize the object (or later), in the defintion file you set up a list of constraints. When you try adding a node to the list the constraints are checked to see if the node is allowed.

How to use

I wrote an example project on how to use the library.


npm i constraint-list-builder --save


npm test

Defining your contraints

Example of constraint structure

        "id": "node1",
        "allowedNodes": ["node2", "node3"]
        //other custom properties
        "id": "node2",
        "allowedNodes": ["node1"]
        //other custom properties
        "id": "node3",
        "allowedNodes": ["node4"]
        //other custom properties
        "id": "node4",
        "allowedNodes": []
        //other custom properties


Fields explained

id - id of the node

allowedNodes - array of ids of the nodes that are allowed to be added after the current node.

In the above example if you've added node1 to the list you can only add node2 or node3. node4 cannot be added. Since node4 does not allow any nodes to be added if node4 is ever added to the list, no other nodes can be added after it.

Huge thanks to:

tsmean - for their excellent article - for their article on setting up unit tests


  • More unit test.
  • update Defining your contraints, remove name.
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