Class HDict

Create a dict using a set of object values.

There are multiple ways to create a dict...

// Create an empty dict
const dict0 = new HDict()

// Create a dict from a bunch of key haystack value pairs
const dict1 = new HDict({ foo: HStr.make('foovalue;), boo: HNum.make(123) })

// Same but with Hayson
const dict2 = new HDict({ foo: 'foovalue', boo: 123 })

// Create a grid from any haystack value...
const dict3 = new HDict(HStr.make('foovalue')) // Create with one row and one column as 'val'.
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If this dict is for a def then return its name otherwise return an empty string.

for (let key of dict.keys) {
  console.log(key)
}
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console.log('Size: ' + dict.length)
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for (let value of dict.values) {
  console.log(value.getKind())
}
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Iterate over a dict.

This enables a 'for ... of' loop to be used directly on an iterator.

Return true if the dict matches the specified filter or if the value exists in the dict at least once.

if (dict.any('site and geoCity == "London"')) {
  ...
}
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Throws

An error for a invalid haystack filter.

Clear all entries from the dict.

// Clear all the entries from the dict.
dict.clear()
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Compares two values.

Create a diff (difference) dict that can be used in an update.

This will return a new dict with any changed values and removed tags having an HRemove value.

Value equality check.

Returns a haystack value from the dict or undefined if it can't be found.

// Gets the value as an HVal so cast to an HStr.
const str = dict.get('foo') as HStr

if (str) {
  // Do something.
}

// Method is generic to make it easier on the eye for casting.
const str1 = dict.get<HStr>('foo')
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Returns true if the dict has the specified key.

if (dict.has('foo')) {
  // Do something
}
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Dump the value to the local console output.

if (dict.isEmpty()) {
  // There are no entries in the dict.
}
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Compares the value's kind.

Returns true if this dict is newer than the specified dict. The mod timestamp is used to perform the check.

Returns true if the haystack filter matches the value.

This method is the same as any.

if (dict.matches('site and geoCity == "London"')) {
  // Do something
}
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Return a reflected array of children prototypes.

If a namespace isn't specified then the default environment namespace will be used.

Analyze this dict and return its implemented defs.

If a namespace isn't specified then the default environment namespace will be used.

Removes a property from the dict.

// Removes the tag named foo.
dict.remove('foo')
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Set a haystack value.

dict.set('foo', HStr.make('New value'))

// Set the value using Hayson
dict.set('foo', 'New value')
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Get the display string for the dict or the given tag. If 'name' is undefined, then return display text for the entire dict. If 'name' is non-null then format the tag value. If 'name' is not defined by this dict then return 'def'.

// Returns the record's dis tag string value...
myDict.toDis()

// Returns the record's tag value string value for foo...
myDict.toDis({ name: 'foo' })

// Returns a localized string based on `disKey`...
myDict.toDis({
  i18n: (pod: string, key: string): string | undefined => pods.get(pod)?.key(key)
})
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See

dictToDis

Encodes to an encoded zinc value that can be used in a haystack filter string.

A dict isn't supported in filter so throw an error.

// Convert the dict to an HGrid with one row.
const hgrid = dict.toGrid()
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// Convert the dict to an HList of haystack strings.
const hlist = dict.toList<HStr>()
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Returns the underlying object being managed by the store.

// Gets a JS Object with the keys as strings and the values as HVals.
const obj = dict.toObj()
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Encodes to an encoding zinc value.

Update a dict from another dict(s) or Hayson dict(s).

dict.update(otherDict, anotherDict)

// Update using a Hayson object
dict.update({ dis: 'A new display string', curVal: 20 })
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Iterates through the dict to ensure we have a valid set of haystack values.

As the dict's internals are directly exposed calling this method will ensure all the values held in the dict are valid haystack values.

Make a dict using a set of object values.

Merge multiple dicts into one.

// The merged dict has all the tags from dict0, dict1 and dict2.
const mergedDict = HDict.merge(dict0, dict1, dict2)
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