Function: to_number

DOC_MSE_VERSION: since 0.3.7

--Usage--
> to_number(any value)

Convert any value to a number.
If the number can be represented as an [[type:int|integer number]] that is done.
Otherwise it is converted to a [[type:double]].


--Parameters--
! Parameter	Type			Description
| @input@	''any type''		Value to convert to a number

--Examples--
> to_number(1)     == 1
> to_number(1.5)   == 1.5
> to_number("1")   == 1
> to_number("1.5") == 1.5

Use @or else@ to recover from errors:
> to_number("not a number") or else 0  ==  0
> to_number("123")          or else 0  ==  123

--See also--
| [[fun:to_int]]		Convert any value to a [[type:int]]
| [[fun:to_real]]		Convert any value to a [[type:double]]