Macro rust_icu_common::format_ustring_for_type

macro_rules! format_ustring_for_type {
    ($method_name:ident, $function_name:ident, $type_decl:ty) => { ... };
}

There is a slew of near-identical method calls which differ in the type of the input argument and the name of the function to invoke.

The invocation:

impl ... {
  // ...
  format_ustring_for_type!(format_f64, unum_formatDouble, f64);
}

allows us to bind the function:

int32_t unum_formatDouble(
    const UNumberFormat* fmt,
    double number,
    UChar* result,
    int32_t result_length,
    UFieldPosition* pos,
    UErrorCode *status)

as:

impl ... {
  format_f64(&self /* format */, value: f64) -> Result<ustring::UChar, common::Error>;
}