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Field

class Field : Selectable

kotlin.Any
↳	com.google.firebase.firestore.pipeline.Expression
	↳	com.google.firebase.firestore.pipeline.Selectable
		↳	com.google.firebase.firestore.pipeline.Field

Represents a reference to a field in a Firestore document.

Field references are used to access document field values in expressions and to specify fields for sorting, filtering, and projecting data in Firestore pipelines.

You can create a Field instance using the static Expression.field method:

Summary

Public functions
`open operator Boolean`	`equals(other: Any?)`
`Expression`	`@Beta geoDistance(location: GeoPoint)` Evaluates to the distance in meters between the location specified by this field and the query location.
`open Int`	`hashCode()`

Inherited functions

From com.google.firebase.firestore.pipeline.Expression

`Expression`	`abs()` Creates an expression that returns the absolute value of this expression.
`Expression`	`add(second: Expression)` Creates an expression that adds this numeric expression to another numeric expression.
`Expression`	`add(second: Number)` Creates an expression that adds this numeric expression to a constants.
`open AliasedExpression`	`alias(alias: String)` Assigns an alias to this expression.
`AggregateFunction`	`arrayAgg()` Creates an aggregation that collects all values of this expression across multiple stage inputs into an array.
`AggregateFunction`	`arrayAggDistinct()` Creates an aggregation that collects all distinct values of this expression across multiple stage inputs into an array.
`Expression`	`arrayConcat(secondArray: Any, vararg otherArrays: Any)` Creates an expression that concatenates a field's array value with other arrays.
`Expression`	`arrayConcat(secondArray: Expression, vararg otherArrays: Any)` Creates an expression that concatenates a field's array value with other arrays.
`BooleanExpression`	`arrayContains(element: Any)` Creates an expression that checks if array contains a specific `element`.
`BooleanExpression`	`arrayContains(element: Expression)` Creates an expression that checks if array contains a specific `element`.
`BooleanExpression`	`arrayContainsAll(arrayExpression: Expression)` Creates an expression that checks if array contains all elements of `arrayExpression`.
`BooleanExpression`	`arrayContainsAll(values: List<Any>)` Creates an expression that checks if array contains all the specified `values`.
`BooleanExpression`	`arrayContainsAny(arrayExpression: Expression)` Creates an expression that checks if array contains any elements of `arrayExpression`.
`BooleanExpression`	`arrayContainsAny(values: List<Any>)` Creates an expression that checks if array contains any of the specified `values`.
`Expression`	`arrayFilter(alias: String, filter: BooleanExpression)` Filters this array expression based on a predicate.
`Expression`	`arrayFirst()` Creates an expression that returns the first element of an array expression.
`Expression`	`arrayFirstN(n: Expression)` Creates an expression that returns the first N elements of an array expression.
`Expression`	`arrayFirstN(n: Int)` Creates an expression that returns the first N elements of an array expression.
`Expression`	`arrayGet(offset: Expression)` Creates an expression that indexes into an array from the beginning or end and return the element.
`Expression`	`arrayGet(offset: Int)` Creates an expression that indexes into an array from the beginning or end and return the element.
`Expression`	`arrayIndexOf(value: Any?)` Creates an expression that returns the first index where the specified `value` occurs in the `array`.
`Expression`	`arrayIndexOfAll(value: Any?)` Creates an expression that returns a list of all indices where the specified `value` occurs in the `array`.
`Expression`	`arrayLast()` Creates an expression that returns the last element of an array expression.
`Expression`	`arrayLastIndexOf(value: Any?)` Creates an expression that returns the last index where the specified `value` occurs in the `array`.
`Expression`	`arrayLastN(n: Expression)` Creates an expression that returns the last N elements of an array expression.
`Expression`	`arrayLastN(n: Int)` Creates an expression that returns the last N elements of an array expression.
`Expression`	`arrayLength()` Creates an expression that calculates the length of an array expression.
`Expression`	`arrayMaximum()` Creates an expression that returns the maximum value of an array expression.
`Expression`	`arrayMaximumN(n: Expression)` Creates an expression that returns the first `n` largest elements of the `array`.
`Expression`	`arrayMaximumN(n: Int)` Creates an expression that returns the first `n` largest elements of the `array`.
`Expression`	`arrayMinimum()` Creates an expression that returns the minimum value of an array expression.
`Expression`	`arrayMinimumN(n: Expression)` Creates an expression that returns the first `n` smallest elements of the `array`.
`Expression`	`arrayMinimumN(n: Int)` Creates an expression that returns the first `n` smallest elements of the `array`.
`Expression`	`arrayReverse()` Reverses the order of elements in the array.
`Expression`	`arraySlice(offset: Expression, length: Expression)` Creates an expression that returns a slice of this array expression.
`Expression`	`arraySlice(offset: Int, length: Int)` Creates an expression that returns a slice of this array expression.
`Expression`	`arraySliceToEnd(offset: Expression)` Creates an expression that returns a slice of this array expression to its end.
`Expression`	`arraySliceToEnd(offset: Int)` Creates an expression that returns a slice of this array expression to its end.
`Expression`	`arraySum()` Creates an expression that returns the sum of the elements in this array expression.
`Expression`	`arrayTransform(elementAlias: String, transform: Expression)` Creates an expression that applies a provided transformation to each element in an array.
`Expression`	`arrayTransformWithIndex( elementAlias: String, indexAlias: String, transform: Expression )` Creates an expression that applies a provided transformation to each element in an array, providing the element's index to the transformation expression.
`BooleanExpression`	`asBoolean()` Casts the expression to a `BooleanExpression`.
`Ordering`	`ascending()` Create an `Ordering` that sorts documents in ascending order based on value of this expression
`AggregateFunction`	`average()` Creates an aggregation that calculates the average (mean) of this numeric expression across multiple stage inputs.
`Expression`	`bitAnd(bitsOther: ByteArray)` Creates an expression that applies a bitwise AND operation with a constant.
`Expression`	`bitAnd(bitsOther: Expression)` Creates an expression that applies a bitwise AND operation with other expression.
`Expression`	`bitLeftShift(number: Int)` Creates an expression that applies a bitwise left shift operation with a constant.
`Expression`	`bitLeftShift(numberExpr: Expression)` Creates an expression that applies a bitwise left shift operation with an expression.
`Expression`	`bitNot()` Creates an expression that applies a bitwise NOT operation to this expression.
`Expression`	`bitOr(bitsOther: ByteArray)` Creates an expression that applies a bitwise OR operation with a constant.
`Expression`	`bitOr(bitsOther: Expression)` Creates an expression that applies a bitwise OR operation with other expression.
`Expression`	`bitRightShift(number: Int)` Creates an expression that applies a bitwise right shift operation with a constant.
`Expression`	`bitRightShift(numberExpr: Expression)` Creates an expression that applies a bitwise right shift operation with an expression.
`Expression`	`bitXor(bitsOther: ByteArray)` Creates an expression that applies a bitwise XOR operation with a constant.
`Expression`	`bitXor(bitsOther: Expression)` Creates an expression that applies a bitwise XOR operation with an expression.
`Expression`	`byteLength()` Creates an expression that calculates the length of a string in UTF-8 bytes, or just the length of a Blob.
`Expression`	`ceil()` Creates an expression that returns the smallest integer that isn't less than this numeric expression.
`Expression`	`charLength()` Creates an expression that calculates the character length of this string expression in UTF8.
`Expression`	`coalesce(replacement: Any, vararg others: Any)` Creates an expression that returns the first non-null, non-absent argument, without evaluating the rest of the arguments.
`Expression`	`collectionId()` Creates an expression that returns the collection ID from this path expression.
`Expression`	`concat(second: Any, vararg others: Any)` Creates an expression that concatenates this expression's value with others.
`Expression`	`concat(second: Expression, vararg others: Any)` Creates an expression that concatenates this expression's value with others.
`Expression`	`cosineDistance(vector: DoubleArray)` Calculates the Cosine distance between this vector expression and a vector literal.
`Expression`	`cosineDistance(vector: Expression)` Calculates the Cosine distance between this and another vector expressions.
`Expression`	`cosineDistance(vector: VectorValue)` Calculates the Cosine distance between this vector expression and a vector literal.
`AggregateFunction`	`count()` Creates an aggregation that counts the number of stage inputs with valid evaluations of the this expression.
`AggregateFunction`	`countDistinct()` Creates an aggregation that counts the number of distinct values of an expression across multiple stage inputs.
`Ordering`	`descending()` Create an `Ordering` that sorts documents in descending order based on value of this expression
`Expression`	`divide(divisor: Expression)` Creates an expression that divides this numeric expression by another numeric expression.
`Expression`	`divide(divisor: Number)` Creates an expression that divides this numeric expression by a constant.
`Expression`	`documentId()` Creates an expression that returns the document ID from this path expression.
`Expression`	`dotProduct(vector: DoubleArray)` Calculates the dot product distance between this vector expression and a vector literal.
`Expression`	`dotProduct(vector: Expression)` Calculates the dot product distance between this and another vector expression.
`Expression`	`dotProduct(vector: VectorValue)` Calculates the dot product distance between this vector expression and a vector literal.
`BooleanExpression`	`endsWith(suffix: Expression)` Creates an expression that checks if this string expression ends with a given `suffix`.
`BooleanExpression`	`endsWith(suffix: String)` Creates an expression that checks if this string expression ends with a given `suffix`.
`BooleanExpression`	`equal(other: Expression)` Creates an expression that checks if this and `other` expression are equal.
`BooleanExpression`	`equal(value: Any)` Creates an expression that checks if this expression is equal to a `value`.
`BooleanExpression`	`equalAny(arrayExpression: Expression)` Creates an expression that checks if this expression, when evaluated, is equal to any of the elements of `arrayExpression`.
`BooleanExpression`	`equalAny(values: List<Any>)` Creates an expression that checks if this expression, when evaluated, is equal to any of the provided `values`.
`Expression`	`euclideanDistance(vector: DoubleArray)` Calculates the Euclidean distance between this vector expression and a vector literal.
`Expression`	`euclideanDistance(vector: Expression)` Calculates the Euclidean distance between this and another vector expression.
`Expression`	`euclideanDistance(vector: VectorValue)` Calculates the Euclidean distance between this vector expression and a vector literal.
`BooleanExpression`	`exists()` Creates an expression that checks if this expression evaluates to a name of the field that exists.
`Expression`	`exp()` Creates an expression that returns Euler's number e raised to the power of this expression.
`AggregateFunction`	`first()` Creates an aggregation that finds the first value of this expression across multiple stage inputs.
`Expression`	`floor()` Creates an expression that returns the largest integer that is not greater than this numeric expression.
`Expression`	`getField(key: String)` Accesses a field/property of a document or Map using the provided `key`.
`Expression`	`getField(keyExpression: Expression)` Accesses a field/property of a document or Map using the provided `keyExpression`.
`BooleanExpression`	`greaterThan(other: Expression)` Creates an expression that checks if this expression is greater than the `other` expression.
`BooleanExpression`	`greaterThan(value: Any)` Creates an expression that checks if this expression is greater than a `value`.
`BooleanExpression`	`greaterThanOrEqual(other: Expression)` Creates an expression that checks if this expression is greater than or equal to the `other` expression.
`BooleanExpression`	`greaterThanOrEqual(value: Any)` Creates an expression that checks if this expression is greater than or equal to a `value`.
`Expression`	`ifAbsent(elseExpr: Expression)` Creates an expression that returns the `elseExpr` argument if this expression is absent, else return the result of this expression.
`Expression`	`ifAbsent(elseValue: Any)` Creates an expression that returns the `elseValue` argument if this expression is absent, else return the result of this expression.
`Expression`	`ifError(catchExpr: Expression)` Creates an expression that returns the `catchExpr` argument if there is an error, else return the result of this expression.
`Expression`	`ifError(catchValue: Any)` Creates an expression that returns the `catchValue` argument if there is an error, else return the result of this expression.
`Expression`	`ifNull(elseExpression: Expression)` Creates an expression that returns the `elseExpression` argument if this expression evaluates to null, else return the result of this expression.
`Expression`	`ifNull(elseValue: Any)` Creates an expression that returns the `elseValue` argument if this expression evaluates to null, else return the result of this expression.
`BooleanExpression`	`isAbsent()` Creates an expression that returns true if the result of this expression is absent.
`BooleanExpression`	`isError()` Creates an expression that checks if this expression produces an error.
`BooleanExpression`	`isType(type: String)` Creates an expression that checks if the result of this expression is of the given type.
`Expression`	`join(delimiter: String)` Creates an expression that joins the elements of an array into a string.
`Expression`	`join(delimiterExpression: Expression)` Creates an expression that joins the elements of an array into a string.
`AggregateFunction`	`last()` Creates an aggregation that finds the last value of this expression across multiple stage inputs.
`Expression`	`length()` Creates an expression that calculates the length of a string, array, map, vector, or blob expression.
`BooleanExpression`	`lessThan(other: Expression)` Creates an expression that checks if this expression is less than the `other` expression.
`BooleanExpression`	`lessThan(value: Any)` Creates an expression that checks if this expression is less than a value.
`BooleanExpression`	`lessThanOrEqual(other: Expression)` Creates an expression that checks if this expression is less than or equal to the `other` expression.
`BooleanExpression`	`lessThanOrEqual(value: Any)` Creates an expression that checks if this expression is less than or equal to a `value`.
`BooleanExpression`	`like(pattern: Expression)` Creates an expression that performs a case-sensitive wildcard string comparison.
`BooleanExpression`	`like(pattern: String)` Creates an expression that performs a case-sensitive wildcard string comparison.
`Expression`	`ln()` Creates an expression that returns the natural logarithm of this numeric expression.
`Expression`	`log10()` Creates an expression that returns the base-10 logarithm of this numeric expression.
`Expression`	`logicalMaximum(vararg others: Any)` Creates an expression that returns the largest value between multiple input expressions or literal values.
`Expression`	`logicalMaximum(vararg others: Expression)` Creates an expression that returns the largest value between multiple input expressions or literal values.
`Expression`	`logicalMinimum(vararg others: Any)` Creates an expression that returns the smallest value between multiple input expressions or literal values.
`Expression`	`logicalMinimum(vararg others: Expression)` Creates an expression that returns the smallest value between multiple input expressions or literal values.
`Expression`	`ltrim()` Creates an expression that removes leading whitespace from this string expression.
`Expression`	`ltrimValue(valuesToTrim: Expression)` Creates an expression that removes a set of leading values from this string expression.
`Expression`	`ltrimValue(valuesToTrim: String)` Creates an expression that removes a set of leading values from this string expression.
`Expression`	`mapEntries()` Creates an expression that returns the entries of this map expression as an array of maps, where each map contains a "k" property for the key and a "v" property for the value.
`Expression`	`mapGet(key: String)` Accesses a map (object) value using the provided `key`.
`Expression`	`mapGet(keyExpression: Expression)` Accesses a map (object) value using the provided `keyExpression`.
`Expression`	`mapKeys()` Creates an expression that returns the keys of this map expression.
`Expression`	`mapMerge(mapExpr: Expression, vararg otherMaps: Expression)` Creates an expression that merges multiple maps into a single map.
`Expression`	`mapRemove(key: String)` Creates an expression that removes a key from this map expression.
`Expression`	`mapRemove(keyExpression: Expression)` Creates an expression that removes a key from this map expression.
`Expression`	`mapSet(key: Expression, value: Expression, vararg moreKeyValues: Expression)` Creates an expression that returns a new map with the specified entries added or updated.
`Expression`	`mapSet(key: String, value: Any?, vararg moreKeyValues: Any)` Creates an expression that returns a new map with the specified entries added or updated.
`Expression`	`mapValues()` Creates an expression that returns the values of this map expression.
`AggregateFunction`	`maximum()` Creates an aggregation that finds the maximum value of this expression across multiple stage inputs.
`AggregateFunction`	`minimum()` Creates an aggregation that finds the minimum value of this expression across multiple stage inputs.
`Expression`	`mod(divisor: Expression)` Creates an expression that calculates the modulo (remainder) of dividing this numeric expressions by another numeric expression.
`Expression`	`mod(divisor: Number)` Creates an expression that calculates the modulo (remainder) of dividing this numeric expressions by a constant.
`Expression`	`multiply(second: Expression)` Creates an expression that multiplies this numeric expression with another numeric expression.
`Expression`	`multiply(second: Number)` Creates an expression that multiplies this numeric expression with a constant.
`BooleanExpression`	`notEqual(other: Expression)` Creates an expression that checks if this expressions is not equal to the `other` expression.
`BooleanExpression`	`notEqual(value: Any)` Creates an expression that checks if this expression is not equal to a `value`.
`BooleanExpression`	`notEqualAny(arrayExpression: Expression)` Creates an expression that checks if this expression, when evaluated, is not equal to all the elements of `arrayExpression`.
`BooleanExpression`	`notEqualAny(values: List<Any>)` Creates an expression that checks if this expression, when evaluated, is not equal to all the provided `values`.
`Expression`	`parent()` Creates an expression that returns the parent document reference of this document reference expression.
`Expression`	`pow(exponent: Expression)` Creates an expression that returns this numeric expression raised to the power of the `exponent`.
`Expression`	`pow(exponent: Number)` Creates an expression that returns this numeric expression raised to the power of the `exponent`.
`BooleanExpression`	`regexContains(pattern: Expression)` Creates an expression that checks if this string expression contains a specified regular expression as a substring.
`BooleanExpression`	`regexContains(pattern: String)` Creates an expression that checks if this string expression contains a specified regular expression as a substring.
`BooleanExpression`	`regexMatch(pattern: Expression)` Creates an expression that checks if this string expression matches a specified regular expression.
`BooleanExpression`	`regexMatch(pattern: String)` Creates an expression that checks if this string expression matches a specified regular expression.
`Expression`	`reverse()` Creates an expression that reverses this string expression.
`Expression`	`round()` Creates an expression that rounds this numeric expression to nearest integer.
`Expression`	`roundToPrecision(decimalPlace: Expression)` Creates an expression that rounds off this numeric expression to `decimalPlace` decimal places if `decimalPlace` is positive, rounds off digits to the left of the decimal point if `decimalPlace` is negative.
`Expression`	`roundToPrecision(decimalPlace: Int)` Creates an expression that rounds off this numeric expression to `decimalPlace` decimal places if `decimalPlace` is positive, rounds off digits to the left of the decimal point if `decimalPlace` is negative.
`Expression`	`rtrim()` Creates an expression that removes trailing whitespace from this string expression.
`Expression`	`rtrimValue(valuesToTrim: Expression)` Creates an expression that removes a set of trailing values from this string expression.
`Expression`	`rtrimValue(valuesToTrim: String)` Creates an expression that removes a set of trailing characters from this string expression.
`Expression`	`split(delimiter: Blob)` Creates an expression that splits this blob expression by a blob delimiter.
`Expression`	`split(delimiter: Expression)` Creates an expression that splits this string or blob expression by a delimiter.
`Expression`	`split(delimiter: String)` Creates an expression that splits this string or blob expression by a string delimiter.
`Expression`	`sqrt()` Creates an expression that returns the square root of this numeric expression.
`BooleanExpression`	`startsWith(prefix: Expression)` Creates an expression that checks if this string expression starts with a given `prefix`.
`BooleanExpression`	`startsWith(prefix: String)` Creates an expression that checks if this string expression starts with a given `prefix`.
`Expression`	`stringConcat(vararg stringExpressions: Expression)` Creates an expression that concatenates string expressions together.
`Expression`	`stringConcat(vararg strings: Any)` Creates an expression that concatenates string expressions and string constants together.
`Expression`	`stringConcat(vararg strings: String)` Creates an expression that concatenates this string expression with string constants.
`BooleanExpression`	`stringContains(substring: Expression)` Creates an expression that checks if this string expression contains a specified substring.
`BooleanExpression`	`stringContains(substring: String)` Creates an expression that checks if this string expression contains a specified substring.
`Expression`	`stringIndexOf(substring: Expression)` Creates an expression that returns the 0-based index of the first occurrence of the specified substring.
`Expression`	`stringIndexOf(substring: String)` Creates an expression that returns the 0-based index of the first occurrence of the specified substring.
`Expression`	`stringRepeat(count: Expression)` Creates an expression that repeats this string expression a given number of times.
`Expression`	`stringRepeat(count: Int)` Creates an expression that repeats this string expression a given number of times.
`Expression`	`stringReplaceAll(oldValue: Expression, newValue: Expression)` Creates an expression that replaces all occurrences of a substring with another string.
`Expression`	`stringReplaceAll(oldValue: String, newValue: String)` Creates an expression that replaces all occurrences of a substring with another string.
`Expression`	`stringReplaceOne(oldValue: Expression, newValue: Expression)` Creates an expression that replaces the first occurrence of a substring with another string.
`Expression`	`stringReplaceOne(oldValue: String, newValue: String)` Creates an expression that replaces the first occurrence of a substring with another string.
`Expression`	`stringReverse()` Creates an expression that performs a reverse operation on this string expression.
`Expression`	`substring(start: Expression, length: Expression)` Creates an expression that returns a substring of the given string.
`Expression`	`substring(start: Int, length: Int)` Creates an expression that returns a substring of the given string.
`Expression`	`subtract(subtrahend: Expression)` Creates an expression that subtracts a constant from this numeric expression.
`Expression`	`subtract(subtrahend: Number)` Creates an expression that subtracts a numeric expressions from this numeric expression.
`AggregateFunction`	`sum()` Creates an aggregation that calculates the sum of this numeric expression across multiple stage inputs.
`Expression`	`timestampAdd(unit: Expression, amount: Expression)` Creates an expression that adds a specified amount of time to this timestamp expression.
`Expression`	`timestampAdd(unit: String, amount: Long)` Creates an expression that adds a specified amount of time to this timestamp expression.
`Expression`	`timestampDiff(start: Expression, unit: Expression)` Calculates the difference between this timestamp and another timestamp.
`Expression`	`timestampDiff(start: Expression, unit: String)` Calculates the difference between this timestamp and another timestamp.
`Expression`	`timestampDiff(startFieldName: String, unit: String)` Calculates the difference between this timestamp and another timestamp.
`Expression`	`timestampExtract(part: Expression)` Creates an expression that extracts a specified part from this timestamp expression.
`Expression`	`timestampExtract(part: String)` Creates an expression that extracts a specified part from this timestamp expression.
`Expression`	`timestampExtractWithTimezone(part: Expression, timezone: Expression)` Creates an expression that extracts a specified part from this timestamp expression in a given timezone.
`Expression`	`timestampExtractWithTimezone(part: Expression, timezone: String)` Creates an expression that extracts a specified part from this timestamp expression in a given timezone.
`Expression`	`timestampExtractWithTimezone(part: String, timezone: Expression)` Creates an expression that extracts a specified part from this timestamp expression in a given timezone.
`Expression`	`timestampExtractWithTimezone(part: String, timezone: String)` Creates an expression that extracts a specified part from this timestamp expression in a given timezone.
`Expression`	`timestampSubtract(unit: Expression, amount: Expression)` Creates an expression that subtracts a specified amount of time to this timestamp expression.
`Expression`	`timestampSubtract(unit: String, amount: Long)` Creates an expression that subtracts a specified amount of time to this timestamp expression.
`Expression`	`timestampToUnixMicros()` Creates an expression that converts this timestamp expression to the number of microseconds since the Unix epoch (1970-01-01 00:00:00 UTC).
`Expression`	`timestampToUnixMillis()` Creates an expression that converts this timestamp expression to the number of milliseconds since the Unix epoch (1970-01-01 00:00:00 UTC).
`Expression`	`timestampToUnixSeconds()` Creates an expression that converts this timestamp expression to the number of seconds since the Unix epoch (1970-01-01 00:00:00 UTC).
`Expression`	`timestampTruncate(granularity: Expression)` Creates an expression that truncates this timestamp expression to a specified granularity.
`Expression`	`timestampTruncate(granularity: String)` Creates an expression that truncates this timestamp expression to a specified granularity.
`Expression`	`timestampTruncateWithTimezone( granularity: Expression, timezone: Expression )` Creates an expression that truncates this timestamp expression to a specified granularity in a given timezone.
`Expression`	`timestampTruncateWithTimezone(granularity: Expression, timezone: String)` Creates an expression that truncates this timestamp expression to a specified granularity in a given timezone.
`Expression`	`timestampTruncateWithTimezone(granularity: String, timezone: Expression)` Creates an expression that truncates this timestamp expression to a specified granularity in a given timezone.
`Expression`	`timestampTruncateWithTimezone(granularity: String, timezone: String)` Creates an expression that truncates this timestamp expression to a specified granularity in a given timezone.
`Expression`	`toLower()` Creates an expression that converts this string expression to lowercase.
`Expression`	`toUpper()` Creates an expression that converts this string expression to uppercase.
`Expression`	`trim()` Creates an expression that removes leading and trailing whitespace from this string expression.
`Expression`	`trimValue(valueToTrim: Expression)` Creates an expression that removes a set of leading and trailing values from this expression.
`Expression`	`trimValue(valueToTrim: String)` Creates an expression that removes a set of leading and trailing values from this string expression.
`Expression`	`trunc()` Creates an expression that truncates this numeric expression to an integer.
`Expression`	`truncToPrecision(decimalPlace: Expression)` Creates an expression that truncates this numeric expression to `decimalPlace` decimal places if `decimalPlace` is positive, truncates digits to the left of the decimal point if `decimalPlace` is negative.
`Expression`	`truncToPrecision(decimalPlace: Int)` Creates an expression that truncates this numeric expression to `decimalPlace` decimal places if `decimalPlace` is positive, truncates digits to the left of the decimal point if `decimalPlace` is negative.
`Expression`	`type()` Creates an expression that returns a string indicating the type of the value this expression evaluates to.
`Expression`	`unixMicrosToTimestamp()` Creates an expression that interprets this expression as the number of microseconds since the Unix epoch (1970-01-01 00:00:00 UTC) and returns a timestamp.
`Expression`	`unixMillisToTimestamp()` Creates an expression that interprets this expression as the number of milliseconds since the Unix epoch (1970-01-01 00:00:00 UTC) and returns a timestamp.
`Expression`	`unixSecondsToTimestamp()` Creates an expression that interprets this expression as the number of seconds since the Unix epoch (1970-01-01 00:00:00 UTC) and returns a timestamp.
`Expression`	`vectorLength()` Creates an expression that calculates the length (dimension) of a Firestore Vector.

Public functions

equals

open operator fun equals(other: Any?): Boolean

geoDistance

@Beta
fun geoDistance(location: GeoPoint): Expression

Evaluates to the distance in meters between the location specified by this field and the query location.

Note: This Expression can only be used within a Search stage.

Parameters
`location: GeoPoint`	Compute distance to this GeoPoint.

hashCode

open fun hashCode(): Int