8 ms·

Best (professional) practice is to use named functions, with lambdas reserved for one-offs which are so genuinely trivial that promoting them to named functions

by aaronem 11y ago

Best (professional) practice is to use named functions, with lambdas reserved for one-offs which are so genuinely trivial that promoting them to named functions would do more to clutter your code than to streamline it. It's telling that, while you do often see Javascript (not JScript, which is a Microsoft product and quite obsolete) developers pull some crazy nonsense with deeply nested lambdas, you almost never see Javascript developers do that in an environment that requires peer code review.

ameen 11y ago
I used JScripters as a short-hand. I'm well aware of the stigma surrounding JScript :P I've come across many JavaScript devs casually using and advising interns, etc to use anon functions to avoid cluttering code. It was almost preached as a design pattern. I was taken aback (as a back-end dev), but given the crazy stuff most JS devs did I just shrugged it is one of the platforms' quirks.
- deleted 11y ago
  [deleted]
- aaronem 11y ago
  JScript isn't a shorthand for Javascript. It's a name for an ill-favored heterodox implementation of ECMAscript. Using it in the fashion you have here will therefore cause knowledgeable engineers to assume you must not know what you're talking about. Of course, you're welcome to continue doing so nonetheless. Using lambdas in the fashion you describe is a dangerously poor practice that, over the long run, produces code that's much harder to maintain than it should be. That's why you don't see it in environments where changes have to pass peer review by experienced Javascript engineers before being accepted into the codebase. Unfortunately, such environments are far from prevalent and the JS dev world lacks rigor even by comparison with web development as a whole, so you see a lot of people abusing lambdas and encouraging others to do likewise. That doesn't make it any less a bad idea.
  - ameen 11y ago
    I totally agree, and my use of JScript(er) has been the first in the last few years, the last was when I was teaching a bunch of school kids about Web technologies. I don't intend to use it again and only arose out of laziness than ignorance. Are there any other such bad practices in the JS dev world? I've only just considered moving onto Node as I've grown disillusioned with Rails and the concept of using a single language across the entire app & mobile (React Native, etc) sounds enticing.
    - aaronem 11y ago
      Javascript is a fun language, but its laissez-faire nature and occasionally weird semantics lend themselves easily to the development of poor practices. Fortunately, there are several linting tools, such as jshint, which analyze code and complain about such things; I'd suggest taking a look at jshint's documentation, which is a veritable catalog of things it's easy to get wrong in JS and have come back later to bite you. I'd suggest even more strongly installing jshint and using it on your code; it's easy (just "npm install -g jshint" and you're off and running) and highly beneficial. I'd also suggest that it's worth your while to take advantage of the JS dev community's excellent culture around automated testing; while that's a slightly more complicated topic, it is only slightly so, and I've found that a solid test suite, plus a coverage tool to ensure it doesn't leave anything out, is even better for improving and maintaining code quality than just a linter by itself -- jshint can catch stylistic and structural errors, but only unit tests will catch logic errors and regressions introduced by a new change. If you're (understandably) bewildered by the variety of testing tools available -- it seems like somebody comes out with a nifty new one every week or so -- then I'd suggest you can hardly go wrong with these: * jshint, as already described * Mocha, a flexible and reliable test framework * Istanbul, a coverage report generator * Grunt, a build tool whose plugin architecture simplifies integrating them For an example of how they work together, you might take a look at https://github.com/aaron-em/same-encoder https://github.com/aaron-em/same-encoder, where I use them all in support of a library providing functionality which I think is neat and probably no one else cares about. No doubt there are much better examples, but none come to mind quite so readily, and this codebase being as small as it is, it should be able to serve as a decent overview without being so big you'll get bogged down in it. In particular, /Gruntfile.js demonstrates how to tie all these disparate tools together for quick invocation with a single command like 'grunt validate', which I find makes it a lot more likely I will actually remember to run them; also take a look in /test/unit for an example of how Mocha tests are actually written.

by aaronem 11y ago

ameen 11y ago

I used JScripters as a short-hand. I'm well aware of the stigma surrounding JScript :P I've come across many JavaScript devs casually using and advising interns, etc to use anon functions to avoid cluttering code. It was almost preached as a design pattern. I was taken aback (as a back-end dev), but given the crazy stuff most JS devs did I just shrugged it is one of the platforms' quirks.

deleted 11y ago
[deleted]
aaronem 11y ago
JScript isn't a shorthand for Javascript. It's a name for an ill-favored heterodox implementation of ECMAscript. Using it in the fashion you have here will therefore cause knowledgeable engineers to assume you must not know what you're talking about. Of course, you're welcome to continue doing so nonetheless. Using lambdas in the fashion you describe is a dangerously poor practice that, over the long run, produces code that's much harder to maintain than it should be. That's why you don't see it in environments where changes have to pass peer review by experienced Javascript engineers before being accepted into the codebase. Unfortunately, such environments are far from prevalent and the JS dev world lacks rigor even by comparison with web development as a whole, so you see a lot of people abusing lambdas and encouraging others to do likewise. That doesn't make it any less a bad idea.
- ameen 11y ago
  I totally agree, and my use of JScript(er) has been the first in the last few years, the last was when I was teaching a bunch of school kids about Web technologies. I don't intend to use it again and only arose out of laziness than ignorance. Are there any other such bad practices in the JS dev world? I've only just considered moving onto Node as I've grown disillusioned with Rails and the concept of using a single language across the entire app & mobile (React Native, etc) sounds enticing.
  - aaronem 11y ago
    Javascript is a fun language, but its laissez-faire nature and occasionally weird semantics lend themselves easily to the development of poor practices. Fortunately, there are several linting tools, such as jshint, which analyze code and complain about such things; I'd suggest taking a look at jshint's documentation, which is a veritable catalog of things it's easy to get wrong in JS and have come back later to bite you. I'd suggest even more strongly installing jshint and using it on your code; it's easy (just "npm install -g jshint" and you're off and running) and highly beneficial. I'd also suggest that it's worth your while to take advantage of the JS dev community's excellent culture around automated testing; while that's a slightly more complicated topic, it is only slightly so, and I've found that a solid test suite, plus a coverage tool to ensure it doesn't leave anything out, is even better for improving and maintaining code quality than just a linter by itself -- jshint can catch stylistic and structural errors, but only unit tests will catch logic errors and regressions introduced by a new change. If you're (understandably) bewildered by the variety of testing tools available -- it seems like somebody comes out with a nifty new one every week or so -- then I'd suggest you can hardly go wrong with these: * jshint, as already described * Mocha, a flexible and reliable test framework * Istanbul, a coverage report generator * Grunt, a build tool whose plugin architecture simplifies integrating them For an example of how they work together, you might take a look at https://github.com/aaron-em/same-encoder https://github.com/aaron-em/same-encoder, where I use them all in support of a library providing functionality which I think is neat and probably no one else cares about. No doubt there are much better examples, but none come to mind quite so readily, and this codebase being as small as it is, it should be able to serve as a decent overview without being so big you'll get bogged down in it. In particular, /Gruntfile.js demonstrates how to tie all these disparate tools together for quick invocation with a single command like 'grunt validate', which I find makes it a lot more likely I will actually remember to run them; also take a look in /test/unit for an example of how Mocha tests are actually written.