Notes

Background

1This is not completely true: there are a few minor breaking changes that don’t affect code on the web. These are detailed in section D.1 and section E.1 of the ES6 specification.↩

2Source: Tweet by Allen Wirfs-Brock. https://twitter.com/awbjs/status/574649464687734785[↩]($27d2110fdb4d1c9a.md#fnref-faq_1)

Data

1[Speaking JS] parseFloat() in (“Speaking JavaScript”).↩

2[Speaking JS] parseInt() in (“Speaking JavaScript”).↩

3[Speaking JS] The details of rounding errors are explained in “Speaking JavaScript”.↩

4Internally, JavaScript has two zeros. Math.sign(-0) produces the result -0 and Math.sign(+0) produces the result +0.↩

5Iterables are explained in another chapter.↩

6Explained in the chapter on Arrays.↩

Modularity

1The exceptions are function expressions and object literals, which you have to put in parentheses, because they look like function declarations and code blocks.↩

2[Spec] Sect. “Imports” starts with grammar rules and continues with semantics.↩

3[Spec] The specification method GetExportedNames() collects the exports of a module. In step (7.d.i), a check prevents other modules’ default exports from being re-exported.↩

4[Spec] Sect. “Exports” starts with grammar rules and continues with semantics.↩

Collections

1[Speaking JS] “Pitfalls: Using an Object as a Map”↩

2Based on “Closing iterators”, slides by David Herman.↩

3throw() is also an optional method, but is practically never used for iterators and therefore explained in the chapter on generators)↩

4“Combinator” (in HaskellWiki) describes what combinators are.↩

5Or rather, the function counts up until the number start overflows and becomes Infinity, at which point it doesn’t change, anymore.↩