Type Alias ImportMap

Example

suppose that you have the following import map:

const myImportMap: ImportMap = {
	"@scope/lib/some-entry": "https://jsr.io/@oazmi/kitchensink/0.9.2/src/array2d.ts", // this should require the http plugin to resolve
	"type-definitions"     : "jsr:@oazmi/kitchensink@0.9.2/typedefs", // this should require the jsr plugin to resolve
	"build-cli/"           : "jsr:@oazmi/build-tools@0.2.4/cli/",     // reference to a whole directory
}
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then, with this import map, you should hypothetically be able to reference these libraries in your code as the following when bundling:

import { transposeArray2D }            from "@scope/lib/some-entry"
import { Optional, MethodsOf }         from "type-definitions"
import type { CliArgs as DocsCliArgs } from "build-cli/docs.ts" // the prefix is part of the import map
import type { CliArgs as DistCliArgs } from "build-cli/dist.ts" // the prefix is part of the import map

// your code...
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Rules for import maps

here are some rules that your import map record should follow: (copied from MDN):

• none of the keys may be empty.
• all of the values must be strings, defining either a valid absolute url or a valid relative url string that starts with "/", "./", or "../".
• if a key ends with "/", then the corresponding value must also end with "/". a key with a trailing "/" can be used as a prefix for when mapping (or remapping) modules addresses.
• the object properties' ordering is irrelevant; if multiple keys can match the module specifier, the most specific key is used. in other words, a specifier "olive/branch/" would match before "olive/".
• any path that is being matched against an import-map will be normalized before being matched. this means that the path "./foo/../js/app.js" will be normalized and transformed to "./js/app.js", before a suitable match is looked up in the import-map.
• your import-map's keys should be always be pre-normalized. this is because a non-normalized key, such as "hello/earth/../to/./this/world.txt", will never match any possible input path, because the input path will always be normalized first, thereby becoming un-matchable with any un-normalized key. so, the correct thing to do would be to ensure that your import-map keys are normalize before hand. (in the example here, the normalized version of the key would be "hello/to/this/world.txt")