diff options
Diffstat (limited to 'src/util.js')
-rw-r--r-- | src/util.js | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/util.js b/src/util.js new file mode 100644 index 000000000..d2e63b090 --- /dev/null +++ b/src/util.js @@ -0,0 +1,68 @@ +/** Copy own-properties from `props` onto `obj`. + * @returns obj + * @private + */ +export function extend(obj, props) { + if (props) { + for (let i in props) obj[i] = props[i]; + } + return obj; +} + + +/** Fast clone. Note: does not filter out non-own properties. + * @see https://esbench.com/bench/56baa34f45df6895002e03b6 + */ +export function clone(obj) { + return extend({}, obj); +} + + +/** Get a deep property value from the given object, expressed in dot-notation. + * @private + */ +export function delve(obj, key) { + for (let p=key.split('.'), i=0; i<p.length && obj; i++) { + obj = obj[p[i]]; + } + return obj; +} + + +/** @private is the given object a Function? */ +export function isFunction(obj) { + return 'function'===typeof obj; +} + + +/** @private is the given object a String? */ +export function isString(obj) { + return 'string'===typeof obj; +} + + +/** Convert a hashmap of CSS classes to a space-delimited className string + * @private + */ +export function hashToClassName(c) { + let str = ''; + for (let prop in c) { + if (c[prop]) { + if (str) str += ' '; + str += prop; + } + } + return str; +} + + +/** Just a memoized String#toLowerCase */ +let lcCache = {}; +export const toLowerCase = s => lcCache[s] || (lcCache[s] = s.toLowerCase()); + + +/** Call a function asynchronously, as soon as possible. + * @param {Function} callback + */ +let resolved = typeof Promise!=='undefined' && Promise.resolve(); +export const defer = resolved ? (f => { resolved.then(f); }) : setTimeout; |