Struct UniqueFn 

pub struct UniqueFn;

Trait Implementations

impl Debug for UniqueFn

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Function for UniqueFn

Returns distinct rows or columns from a range.

UNIQUE preserves first-occurrence order and can optionally return only values that appear once.

Remarks

• Defaults: by_col=FALSE, exactly_once=FALSE.
• With by_col=FALSE, uniqueness is evaluated by full rows.
• With by_col=TRUE, uniqueness is evaluated by full columns.
• With exactly_once=TRUE, only entries with frequency 1 are returned.
• Result spills as an array.

Examples

title: "Unique values by row"
grid:
  A1: "A"
  A2: "A"
  A3: "B"
  A4: "C"
formula: '=UNIQUE(A1:A4)'
expected: [["A"],["B"],["C"]]

title: "Only values that appear once"
grid:
  A1: 1
  A2: 1
  A3: 2
  A4: 3
formula: '=UNIQUE(A1:A4,FALSE,TRUE)'
expected: [[2],[3]]

related:
  - FILTER
  - SORT
  - SORTBY
faq:
  - q: "What does exactly_once=TRUE change?"
    a: "Instead of returning first occurrences, UNIQUE returns only rows or columns whose full key appears exactly one time."
  - q: "How does by_col affect uniqueness checks?"
    a: "by_col=FALSE compares entire rows, while by_col=TRUE compares entire columns and spills unique columns."

[formualizer-docgen:schema:start] Name: UNIQUE Type: UniqueFn Min args: 1 Max args: variadic Variadic: true Signature: UNIQUE(arg1: range@range, arg2?: logical@scalar, arg3?…: logical@scalar) Arg schema: arg1{kinds=range,required=true,shape=range,by_ref=true,coercion=None,max=None,repeating=None,default=false}; arg2{kinds=logical,required=false,shape=scalar,by_ref=false,coercion=Logical,max=None,repeating=None,default=true}; arg3{kinds=logical,required=false,shape=scalar,by_ref=false,coercion=Logical,max=None,repeating=None,default=true} Caps: PURE [formualizer-docgen:schema:end]

fn caps(&self) -> FnCaps

Capability flags for this function

fn name(&self) -> &'static str

fn min_args(&self) -> usize

fn variadic(&self) -> bool

fn arg_schema(&self) -> &'static [ArgSchema]

fn eval<'a, 'b, 'c>( &self, args: &'c [ArgumentHandle<'a, 'b>], _ctx: &dyn FunctionContext<'b>, ) -> Result<CalcValue<'b>, ExcelError>

The unified evaluation path.

fn namespace(&self) -> &'static str

fn volatile(&self) -> bool

fn aliases(&self) -> &'static [&'static str]

Optional list of additional alias names (case-insensitive) that should resolve to this function. Default: empty slice. Implementors can override to expose legacy names. Returned slice must have ’static lifetime (typically a static array reference).

fn function_salt(&self) -> u64

fn eval_reference<'a, 'b, 'c>( &self, _args: &'c [ArgumentHandle<'a, 'b>], _ctx: &dyn FunctionContext<'b>, ) -> Option<Result<ReferenceType, ExcelError>>

Optional reference result path. Only called by the interpreter/engine when the callsite expects a reference (e.g., range combinators, by-ref argument positions, or spill sources).

fn dispatch<'a, 'b, 'c>( &self, args: &'c [ArgumentHandle<'a, 'b>], ctx: &dyn FunctionContext<'b>, ) -> Result<CalcValue<'b>, ExcelError>

Dispatch to the unified evaluation path with automatic argument validation.