FilterField extension type

A type-safe field identifier for filtering operations.

This extension type wraps a String to provide compile-time type safety when specifying fields in filter operations. It implements String, making it transparent and zero-cost at runtime while ensuring only valid fields can be used in filter operations.

Supported Operators

All filter fields support the following operators:

Comparison: .equal, .greater, .greaterOrEqual, .less, .lessOrEqual
List: .in_, .contains
Existence: .exists
Evaluation: .query, .autoComplete
Path: .pathExists
Logical: .and, .or

Example implementation:

extension type const MyFilterField(String remote) implements FilterField {
  /// Filter by unique identifier.
  ///
  /// **Supported operators**: `.equal`, `.in_`
  static const id = MyFilterField('id');

  /// Filter by display name.
  ///
  /// **Supported operators**: `.equal`, `.query`, `.autoComplete`
  static const name = MyFilterField('name');

  /// Filter by numeric age value.
  ///
  /// **Supported operators**: `.equal`, `.greater`, `.greaterOrEqual`, `.less`, `.lessOrEqual`
  static const age = MyFilterField('age');

  /// Filter by creation timestamp.
  ///
  /// **Supported operators**: `.equal`, `.greater`, `.greaterOrEqual`, `.less`, `.lessOrEqual`
  static const createdAt = MyFilterField('created_at');

  /// Filter by tag collections.
  ///
  /// **Supported operators**: `.in_`, `.contains`
  static const tags = MyFilterField('tags');

  /// Filter by JSON metadata existence.
  ///
  /// **Supported operators**: `.exists`, `.pathExists`
  static const metadata = MyFilterField('metadata');
}

on

String

Implemented types

String

Implementers

Available extensions

StringToJSString

Constructors

FilterField(String _)

Properties

codeUnits → List<int>: An unmodifiable list of the UTF-16 code units of this string.
no setterinherited
hashCode → int: A hash code derived from the code units of the string.
no setterinherited
isEmpty → bool: Whether this string is empty.
no setterinherited
isNotEmpty → bool: Whether this string is not empty.
no setterinherited
length → int: The length of the string.
no setterinherited
runes → Runes: An Iterable of Unicode code-points of this string.
no setterinherited
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
toJS → JSString: Available on String, provided by the StringToJSString extension
Converts this String to a JSString.
no setter

Methods

allMatches(String string, [int start = 0]) → Iterable<Match>: Matches this pattern against the string repeatedly.
inherited
codeUnitAt(int index) → int: Returns the 16-bit UTF-16 code unit at the given index.
inherited
compareTo(String other) → int: Compares this string to other.
inherited
contains(Pattern other, [int startIndex = 0]) → bool: Whether this string contains a match of other.
inherited
endsWith(String other) → bool: Whether this string ends with other.
inherited
indexOf(Pattern pattern, [int start = 0]) → int: Returns the position of the first match of pattern in this string, starting at start, inclusive:
inherited
lastIndexOf(Pattern pattern, [int? start]) → int: The starting position of the last match pattern in this string.
inherited
matchAsPrefix(String string, [int start = 0]) → Match?: Matches this pattern against the start of string.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
padLeft(int width, [String padding = ' ']) → String: Pads this string on the left if it is shorter than width.
inherited
padRight(int width, [String padding = ' ']) → String: Pads this string on the right if it is shorter than width.
inherited
replaceAll(Pattern from, String replace) → String: Replaces all substrings that match from with replace.
inherited
replaceAllMapped(Pattern from, String replace(Match match)) → String: Replace all substrings that match from by a computed string.
inherited
replaceFirst(Pattern from, String to, [int startIndex = 0]) → String: Creates a new string with the first occurrence of from replaced by to.
inherited
replaceFirstMapped(Pattern from, String replace(Match match), [int startIndex = 0]) → String: Replace the first occurrence of from in this string.
inherited
replaceRange(int start, int? end, String replacement) → String: Replaces the substring from start to end with replacement.
inherited
split(Pattern pattern) → List<String>: Splits the string at matches of pattern and returns a list of substrings.
inherited
splitMapJoin(Pattern pattern, {String onMatch(Match)?, String onNonMatch(String)?}) → String: Splits the string, converts its parts, and combines them into a new string.
inherited
startsWith(Pattern pattern, [int index = 0]) → bool: Whether this string starts with a match of pattern.
inherited
substring(int start, [int? end]) → String: The substring of this string from start, inclusive, to end, exclusive.
inherited
toLowerCase() → String: Converts all characters in this string to lower case.
inherited
toString() → String: A string representation of this object.
inherited
toUpperCase() → String: Converts all characters in this string to upper case.
inherited
trim() → String: The string without any leading and trailing whitespace.
inherited
trimLeft() → String: The string without any leading whitespace.
inherited
trimRight() → String: The string without any trailing whitespace.
inherited

Operators

operator *(int times) → String: Creates a new string by concatenating this string with itself a number of times.
inherited
operator +(String other) → String: Creates a new string by concatenating this string with other.
inherited
operator ==(Object other) → bool: Whether other is a String with the same sequence of code units.
inherited
operator [](int index) → String: The character (as a single-code-unit String) at the given index.
inherited