Support string parameters for methods

[spyoungtech]

The methods in Tempus are typically terse about the input type parameter.

For example:

tempus.ahk/tempus.ahk

Lines 2335 to 2342 in fd8112c

	checked_add(other) {
	out_date := Buffer(A_PtrSize)
	if (other is Span) {
	retcode := DllCall("tempus_ahk\date_checked_add_span", "Ptr", this.pointer, "Ptr", other.pointer, "Ptr", out_date, "Int64")
	} else if (other is SignedDuration) {
	retcode := DllCall("tempus_ahk\date_checked_add_signed_duration", "Ptr", this.pointer, "Ptr", other.pointer, "Ptr", out_date, "Int64")
	} else {
	throw Error("Unsupported type. Must be Span or SignedDuration", -2)

However, the ergonomics of the library may be improved if string arguments could be accepted where the desired type can be parsed from a string.

For example:

#Include "tempus.ahk"

ts := Timestamp.now()
span1 := Span.new().hours(2).minutes(30)

ts.checked_add(span1)

Could become:

#Include "tempus.ahk"

ts := Timestamp.now()
ts.checked_add("2h 30m")

Using the same example as above, this could perhaps be implemented roughly as so:

 checked_add(other) { 
     out_date := Buffer(A_PtrSize) 
     if (other is Span) { 
         retcode := DllCall("tempus_ahk\date_checked_add_span", "Ptr", this.pointer, "Ptr", other.pointer, "Ptr", out_date, "Int64") 
     } else if (Type(other) == "String") {
        ; actual implementation will probably need a try/catch, but for brevity, we'll omit it
        return this.checked_add(Span.parse(other))
}

This same kind of principle could be applied in many methods.