isValueColumn

Returns true if this column is a ValueColumn, i.e., its kind is ColumnKind.Value.

This function has a contract: when it returns true, the compiler smart-casts this column to ValueColumn<*>.

See also isColumnGroup, isFrameColumn.

Use asValueColumn to cast a column to ValueColumn<*> without the check.

Examples

val age: AnyCol = df["age"]
if (age.isValueColumn()) {
    // `age` is smart-cast to `ValueColumn<*>` here
    age.distinct() // returns a `ValueColumn` with 15, 45, 20, 40, 30, 18
}