The docs say that the "display" function is built-in, but built-in to what?

[ttmc]

In the Observable Framework docs (with source at https://github.com/observablehq/framework/blob/main/docs/javascript/display.md ), it says, "The built-in display function displays the specified value."

I don't know where the display function is coming from. It's not part of standard JavaScript AFAIK, so it's not "built-in to standard JavaScript". I gather that Observable Framework imports a bunch of libraries by default, so I wonder where the display function is coming from.

[mbostock]

It’s built-in to Observable Framework. I’m not sure if this answers your question, but it’s implemented as a “shadow” variable using the Observable Runtime; each code block has its own display function that is uniquely bound to its output location. You can find the implementation here:

framework/src/client/main.js

Lines 52 to 55 in c114f88

	shadow: {
	display: () => display,
	view: () => (v) => Generators.input(display(v))
	}