This is a TO DO document for modules under the Uize.Data namespace.
1. Uize.Data.safeLookup
|
performs a lookup in a lookup object that may not be a safe lookup, so it handles the problems keys |
|
perhaps there should also be a similar Uize.Data.keyIn (or Uize.Data.keyExists) method |
1.1. - possible implementation
var _problemKeys = {constructor:1,toString:1,valueOf:1};
Uize.Data.safeLookup = function (_lookup,_key) {
if (_problemKeys [_key]) {
var
_value = _lookup [_key],
_lookupConstructor = _lookup.constructor
;
return _lookupConstructor && _value == _lookupConstructor.prototype [_key] ? _undefined : _value;
} else {
return _lookup [_key];
}
};
Uize.Data.makeValueTransformerGenerator = function (_valueTransformer) {
_valueTransformer = Uize.resolveTransformer (_valueTransformer);
var _generator = function () {
if (arguments.length) {
var _arguments = Uize.push ([0],arguments);
return function (_value) {
_arguments [0] = _value;
return _valueTransformer.apply (0,_arguments);
};
} else {
return _valueTransformer;
}
};
_generator.exec = _valueTransformer;
return _generator;
};
2. Uize.Data.resolveSourceAndTarget
_package.resolveSourceAndTarget = function (_source,_target,_targetDefault,_keysMayChange,_emptyOutTarget) {
if (_target === _undefined) _target = _targetDefault;
if (typeof _source == 'number') {
_source = new Array (_source);
if (typeof _target != 'object') _target = _source;
} else if (typeof _target != 'object') {
_target = !_target ? _source : Uize.isArray (_source) ? [] : {};
}
if (_keysMayChange && _target == _source)
_source = Uize.isArray (_source) ? _source.concat () : Uize.copy (_source)
;
_target != _source && _emptyOutTarget && Uize.emptyOut (_target);
return {source:_source,target:_target};
};
usage...
var _sourceAndTarget = Uize.Data.resolveSourceAndTarget (_source,_target,true);
_source = _sourceAndTarget._source;
_target = _sourceAndTarget._target;
3. Uize.Data.hasCircularity
|
tests to see if the object contains circular references / reference loops |
|
for implementation, use object tagging |
4. Uize.Data.mapKeys
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lets you rename keys in an object |
5. Uize.Data.mapKeyValues
|
lets you rename keys and transform values in an object |