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ryū

num.ryū

§(T 
type
)
:
Any
 is


An implementation of Ryū, a fast float to string conversion algorithm invented by Ulf Adams.
For more information see the original repository: https://github.com/ulfjack/ryu
and the paper: https://dl.acm.org/citation.cfm?doid=3296979.3192369

NYI lacks documentation

Value Constructors

§(accept_upper_bound Unary bool bool, accept_lower_bound Unary bool bool)
:
Any
 is
constructor for rounding mode
see below for predefined rounding modes

Functions

§
:
Any
 => 
String 
[Inherited from  Any]
create a String from this instance. Unless redefined, `a.as_string` will
create `"instance[T]"` where `T` is the dynamic type of `a`
§(val num.ryū.T)
:
Any
 => 
String
convert float to string using conservative rounding

if the absolute value
is smaller than 0.001
or greater than 9_999_999
scientific notation will be used.
§(val num.ryū.T, scientific_notation bool, rounding_mode (num.this.ryū.this num.ryū.T).rounding_mode)
:
Any
 => 
String
convert float to string
§
:
Any
 => 
Type 
[Inherited from  Any]
Get the dynamic type of this instance. For value instances `x`, this is
equal to `type_of x`, but for `x` with a `ref` type `x.dynamic_type` gives
the actual runtime type, while `type_of x` results in the static
compile-time type.

There is no dynamic type of a type instance since this would result in an
endless hierarchy of types. So for Type values, dynamic_type is redefined
to just return Type.type.
§
:
Any
 => 
String 
[Inherited from  Any]
convenience prefix operator to create a string from a value.

This permits usage of `$` as a prefix operator in a similar way both
inside and outside of constant strings: $x and "$x" will produce the
same string.
rounding mode 'conservative', never accepts lower/upper bound
rounding mode 'even', chooses the closest even number.
examples: 0.5 => 0

Value Types

constructor for rounding mode
see below for predefined rounding modes

Type Features

§
:
Any
 is
 
[Inherited from  Type]
string representation of this type to be used for debugging.

result has the form "Type of '<name>'", but this might change in the future

redefines:

§
:
Any
 is
 
[Inherited from  Type]
There is no dynamic type of a type instance since this would result in an
endless hierarchy of types, so dynamic_type is redefined to just return
Type.type here.

redefines:

§(T 
type
)
:
Any
 is
 
[Inherited from  Type]
Is this type assignable to a type parameter with constraint `T`?

The result of this is a compile-time constant that can be used to specialize
code for a particular type.

is_of_integer_type(n T : numeric) => T : integer
say (is_of_integer_type 1234) # true
say (is_of_integer_type 3.14) # false

it is most useful in conjunction preconditions or `if` statements as in

pair(a,b T) is

=>

or

val(n T) is

§
:
Any
 is
 
[Inherited from  Type]
name of this type, including type parameters, e.g. 'option (list i32)'.
§
:
Any
 is
 
[Inherited from  Any]
Get a type as a value.

This is a feature with the effect equivalent to Fuzion's `expr.type` call tail.
It is recommended to use `expr.type` and not `expr.type_value`.

`type_value` is here to show how this can be implemented and to illustrate the
difference to `dynamic_type`.