tc39 / proposal-string-left-right-trim Goto Github PK

Is it the same functions? If the same - which names they should have?

String.prototype.trimStart === String.prototype.trimLeft; // ???
String.prototype.trimStart.name; // ???
String.prototype.trimLeft.name; // ???

Per discussion around tc39/proposal-string-pad-start-end@35f1ef6 the committee decided it would be ideal to also provide trimStart and trimEnd - not necessarily in Annex B - so that the language's official naming conventions for strings trended towards start/end instead of left/right.

See tc39/proposals#44

Just some stuff I think we should do before the next meeting

• Update readme
• Update markdown version to the new spec
• Add gh-pages with a rendered version of this proposal
• Close #3 and #4, they seem to be resolved with my new proposal
• Get this scheduled for the next meeting
• Rename this proposal for start/end?
• Add test262 test
• Open a pull request to ecma262

@ljharb Can you think of anything else?

I reviewed the spec text and this is good for Stage 3.

I believe @spectranaut can confirm the same.

In C# you can very handily use .TrimStart("?"), this will remove specifically a "?" if it is at the beginning. This can be incredibly useful for very common cases where you want to remove starting string characters such as dealing with query urls on the web.
JS eg:

var query = ...;
if(query.indexOf("?") === -1)
    query = query.slice(1);

C# eg:
var query = (...).TrimStart("?");

Not sure if this has already been considered, just been using it a lot lately in C# and thought to check if it could be used in JS.

Criteria taken from the TC39 process document minus those from previous stages:

• Test262 acceptance tests have been written for mainline usage scenarios, and merged

PR by @spectranaut: tc39/test262#1246

• Two compatible implementations which pass the acceptance tests

https://github.com/tc39/proposal-string-left-right-trim#implementations

• Significant in-the-field experience with shipping implementations, such as that provided by two independent VMs

https://github.com/tc39/proposal-string-left-right-trim#implementations

• A pull request has been sent to https://github.com/tc39/ecma262 with the integrated spec text

PR by @evilpie: tc39/ecma262#1275

• The ECMAScript editor has signed off on the pull request

We should decide which is more important: compatibility or good design?

Left is not allways Start in multilingual text. This is my proposal:

But understand it's not that easy to decide when dealing with bidirectional strings.