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Groups > comp.lang.javascript > #39739

Re: Exposing a module in the current scope

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Anton Shepelev wrote:

> It looks like in the system for which I need to write
> server-side JavaScript, neither CommonJS nor ECMAScript
> modules are supported, but it provides its own module system
> that works as shown below:
> 
>    $.import("anton_test/util.xsjslib","util"); // import module
>    $.anton_test.util.log("Log from library."); // invoke a function
> 
> Is it somehow possible to have all the functions from `util'
> available in the current scope, so that I could invoke them
> by their names: log("Hello"),

I think you mean the _local execution context_ instead, as the current scope 
is somewhat loosely defined as it extends to the global execution context.

Modules were introduced precisely to avoid the problems that your wish 
typically produces (what if there is a log() etc. defined in the execution 
context already?).

> rather than, say, util.log("Hello"),

While there is at least one fancy way to do this for several and selected 
properties only (which a custom module system might provide), the simple 
code

  const util = $.anton_test.util;

(or

  var util = $.anton_test.util;

to be backwards-compatible), is literally the best that you can do,
in general.

Note that

  const log = $.anton_test.util.log;

is NOT equivalent because “$.anton_test.util.log()” may use “this” to refer 
to “$.anton_test.util” which will refer to the global object, or (in strict 
mode) be the “undefined” value, if you then call “log()”.  The equivalent 
variant would be

  const log = $.anton_test.util.log.bind($.anton_test.util);

but when emulated for backwards compatibility (and maybe even when 
Function.prototype.bind() is available as a built-in), this comes at the 
price of reduced runtime efficiency when it is is called.  So just to be 
able to write “log” instead of “util.log” hardly appears to be worth it.

-- 
PointedEars
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Thread

Exposing a module in the current scope Anton Shepelev <antonius@freeshell.de> - 2021-03-18 19:21 +0300
  Re: Exposing a module in the current scope Anton Shepelev <anton.txt@gmail.com> - 2021-03-18 23:57 +0300
    Re: Exposing a module in the current scope "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-18 18:45 -0700
      Re: Exposing a module in the current scope Anton Shepelev <anton.txt@g{oogle}mail.com> - 2021-03-19 18:11 +0300
        Re: Exposing a module in the current scope Anton Shepelev <anton.txt@g{oogle}mail.com> - 2021-03-19 19:08 +0300
          Re: Exposing a module in the current scope "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-19 10:51 -0700
            Re: Exposing a module in the current scope Anton Shepelev <anton.txt@gmail.com> - 2021-03-20 13:32 +0300
              Re: Exposing a module in the current scope "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-20 09:53 -0700
        Re: Exposing a module in the current scope "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-19 10:47 -0700
          Re: Exposing a module in the current scope Anton Shepelev <anton.txt@gmail.com> - 2021-03-20 13:51 +0300
            Re: Exposing a module in the current scope "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-20 09:59 -0700
              Re: Exposing a module in the current scope Anton Shepelev <anton.txt@g{oogle}mail.com> - 2021-03-24 20:43 +0300
          Re: Exposing a module in the current scope Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-22 21:14 +0100
            Re: Exposing a module in the current scope "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-22 16:00 -0700
              Re: Exposing a module in the current scope Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-23 01:11 +0100
              Re: Exposing a module in the current scope Anton Shepelev <anton.txt@gmail.com> - 2021-04-04 00:31 +0300
  Re: Exposing a module in the current scope "Michael Haufe (TNO)" <tno@thenewobjective.com> - 2021-03-18 11:30 -0700
  Re: Exposing a module in the current scope Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-22 21:05 +0100
  Re: Exposing a module in the current scope Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-23 01:00 +0100
    Re: Exposing a module in the current scope Anton Shepelev <anton.txt@g{oogle}mail.com> - 2021-03-23 20:06 +0300
      Re: Exposing a module in the current scope Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2021-03-25 20:04 +0100
        Re: Exposing a module in the current scope John G Harris <niam@jghnorth.org.uk.invalid> - 2021-03-26 08:32 +0000
        Re: Exposing a module in the current scope John G Harris <niam@jghnorth.org.uk.invalid> - 2021-03-26 08:48 +0000
  Re: Exposing a module in the current scope Anton Shepelev <anton.txt@g{oogle}mail.com> - 2021-04-13 18:49 +0300

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