javascript - Relative vs. non-relative module import for custom modules -


update[09/12/2017 16:58 est]

added reason why hesitate use natively-supported non-relative import own modules bottom of question.

update[09/12/2017 12:58 est]:

per request, made file structure below reflect actual use case. nested view module requesting utility module somewhere directory tree.

per request

in both typescript , es6, 1 can import custom module by

// relative import { numberutil } './number_util'; // or // non-relative import { numberutil } 'number_util';

and according typescript docs (link), 1 should:

... use relative imports own modules guaranteed maintain relative location @ runtime.

... use non-relative paths when importing of external dependencies.

my problem here have project structure this:

project/   |--utils   |    |--number_util.ts   |--views   |    |--article_page   |         |-- editor_view   |                |--editor_text_area.ts

and when include utils/number_util inside editor_text_area module, import statement looks like: 

import { numberutil } './../../../utils/number_util';

which long , not readable and, worst of all, difficult maintain: whenever need move editor_text_area, have update each these relative paths, when in meantime can use non-relative way of

import { numberutil } 'utils/number_util';

does have suggestions on how best module imports achieve highest readability , maintainability?

but using non-relative way poses problem (other not recommended official docs): if installed npm module has same name module i'm importing? on note, not safe uglier alternative mentioned above.

depending on project tooling , structure, have options.

a) publish part of dependencies stand-alone modules, perhaps in private registry. can install them npm , require them other external dependency.

b) many module systems support sort of path mapping. vue-js webpack template uses webpack's alias feature set @ source code root. typescript supports path mapping too. after introduce mapping can use

import { numberutil } '@/utils/number_util';

this approach introduces private namespace modules. safe, in ever shadow npm module name @ invalid name , therefore cannot exist.

for example, have have these entries in compileroptions:

"baseurl": ".", "paths": {     "@/*": ["*"] }

or if want import modules utils, change mapping "@/*": ["utils/*"] , import using '@/number_util'.

c) thing consider improve project structure. depending on actual project, might make sense apply facade pattern @ 1 point or another. maybe inject dependency editor_text_area instead of letting import itself.


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