If objects/values can be shared throughout a runtime, why do we need to supply a JSContext reference to create them?

[mrmbernardi]

quickjs/docs/docs/developer-guide/intro.md

Lines 10 to 21 in ca0d50d

	## Runtime and contexts
	`JSRuntime` represents a JavaScript runtime corresponding to an
	object heap. Several runtimes can exist at the same time but they
	cannot exchange objects. Inside a given runtime, no multi-threading is
	supported.
	`JSContext` represents a JavaScript context (or Realm). Each
	JSContext has its own global objects and system objects. There can be
	several JSContexts per JSRuntime and they can share objects, similar
	to frames of the same origin sharing JavaScript objects in a
	web browser.

This implies I can pass objects around within the same JS_Runtime

Why then have a signature like this: JSValue JS_NewBool(JSContext *ctx, bool val)

Wouldn't this make more sense: JSValue JS_NewBool(JSRuntime *rt, bool val)

[bnoordhuis]

For primitives, yes; or rather, it doesn't matter.

For objects, no. objectFromAnotherContext instanceof Object is false because each JSContext has its own copy of the standard global objects like Object, Array, Date, etc.

For consistency, everything takes a pointer to JSContext, also because otherwise you get inconsistencies like:

JSValue JS_NewBool(JSRuntime *rt, bool val);

Vs.

JSValue JS_ToBool(JSRuntime *ctx, JSValueConst val);

The latter needs JSContext because the ToBool operation can invoke JS code.