Struct IfErrorFn 

pub struct IfErrorFn;

Trait Implementations

impl Debug for IfErrorFn

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

Formats the value using the given formatter.

impl Function for IfErrorFn

Returns a fallback when the first expression evaluates to any error.

IFERROR(value, value_if_error) is useful for user-friendly error handling.

Remarks

• Any error kind in the first argument triggers the fallback branch.
• Non-error results pass through unchanged.
• Evaluation failures surfaced as interpreter errors are also caught.
• Exactly two arguments are required; other arities return #VALUE!.

Examples

title: "Replace division error"
formula: '=IFERROR(1/0, "n/a")'
expected: "n/a"

title: "Pass through non-error"
formula: '=IFERROR(42, 0)'
expected: 42

related:
  - IFNA
  - IF
  - ISERROR
faq:
  - q: "Does IFERROR catch all error types?"
    a: "Yes. Any error kind in the first argument triggers the fallback value."

[formualizer-docgen:schema:start] Name: IFERROR Type: IfErrorFn Min args: 2 Max args: 2 Variadic: false Signature: IFERROR(arg1: any@scalar, arg2: any@scalar) Arg schema: arg1{kinds=any,required=true,shape=scalar,by_ref=false,coercion=None,max=None,repeating=None,default=false}; arg2{kinds=any,required=true,shape=scalar,by_ref=false,coercion=None,max=None,repeating=None,default=false} 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.