freesewing/markdown/dev/howtos/code/dependencies/en.md

title	for	about
Part dependencies	developers	Shows you how to create dependencies between pattern parts

Part dependencies are set in the pattern configuration, and control the order in which parts are drawn. FreeSewing will make sure that before drafting a part, it will first draft all its dependencies.

Let's look at an example:

dependencies: {
  front: "base",
  back: "base",
  sleeve: ["front", "back"]
}

This could be from a T-shirt pattern where the front and back patterns are very similar, so they both are inheriting a base part. In addition, the sleeve part needs to be drafted after the front and back part because in front and back we store the length of the armhole seam in the store and we need that info to fit the sleevecap to the armhole.

Now if a user requests to draft only the sleeve part, FreeSewing will still draft:

• First the base part
• Then the front and back parts
• Finally the sleeve part

but it will only render the sleeve part, as that's the only thing the user requested.

For inheriting parts, please refer to part inheritance.