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Random_Handler

Random_Handler

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 ref
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[Contains abstract features]

Random_Handler -- abstract source of random numbers

This provides the random number input to be used by the 'random' effect.
Implementation may be dumb sequences of pseudo-random numbers or high-quality
cryptographic random number generators

A Random_Handler contains an immutable state, repeated calls to 'get' result
in the same value. To produce a sequence of different random numbers, 'next'
must be used to create a new instance of 'Random_Handler' before 'get' can be
used to obtain the new random number.

Functions

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 => 
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`
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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.
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Any
 => 
u64 
[Abstract feature]
Return the random number stored in this instance of Random_Handler, in the
range 0..u64.max

NOTE: this feature is pure, i.e., repeated calls on the same target result
in equal results. Use 'next' to get different results.
§
:
Any
 => 
Random_Handler 
[Abstract feature]
create a new instance of Random_Handler containing a new state. Depending
on the quality of this random number generator, this might be a simple
function of the original Random_Handler or it might use an external source
of entropy to create a new instance.
§
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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.

Type Features

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[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:

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[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
)
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[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

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[Inherited from  Type]
name of this type, including type parameters, e.g. 'option (list i32)'.
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[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`.
last changed: 2024-09-18