CoffeeScript to NodeJS

Question

I'm currently attempting to port some old CoffeeScript code over (old project) to native NodeJS; I'm struggling to understand what exactly this is doing? or the equivalent in Node?

  builder.macro_extensions = [
      'iced'
      'nsi'
      'txt'
  ]

  await exec """
    find #{temp} | grep #{(_.map @macro_extensions, (x) -> "-e '\\.#{x}'").join ' '}
  """, {silent:on}, defer e,r
  if e then return cb e

If anyone could point me in the right direction, that'd be perfect!

fardjad · Accepted Answer · 2019-06-19T22:31:02.840

1

Assuming exec returns a promise, the code passes 2 arguments to the exec function, waits for the returned promise to be fulfilled, and sets the variable r to the resolved value.

If anything goes wrong (ie. the promise gets rejected), it sets the variable e to the rejection reason of that promise.

The JS equivalent of that code would be:

builder.macro_extensions = ['iced', 'nsi', 'txt'];

const grepArgs = _.map(
  this.macro_extensions, // or maybe builder.macro_extensions
  x => ` -e '\\.${x}'`,
).join(''); // -e '\.iced' -e '\.nsi' -e '\.txt'

let r;
try {
  r = await exec(`find ${temp} | grep ${grepArgs}`, {silent: on});
} catch (e) {
  return cb(e);
}

// ...

edited Jun 19 '19 at 22:31

answered Jun 19 '19 at 22:15

fardjad

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Thanks for this! although it appears that the `_.map` function doesn't exist? – Curtis Jun 19 '19 at 22:30
I suspect it's a [`lodash`](https://www.npmjs.com/package/lodash) function. You could also write that line like: `builder.macro_extensions.map(x => \` -e '\\.${x}'\`).join('');` – fardjad Jun 19 '19 at 22:32
1

you've saved the day!! – Curtis Jun 19 '19 at 22:36

CoffeeScript to NodeJS

1 Answers1