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Mutable_Array

container.Mutable_Array

(T 
type
, E 
type
:
mutate)
 ref
:
Buffer T, E
 is
[Contains abstract features]
an interface defining a mutable array

Type Parameters

effect used to modify this mutable array

Functions

(t T)
 => 
unit
[Abstract feature]
add an element at the end of the array
 => 
array T
[Inherited from  Buffer]
create immutable array from this buffer
 => 
list T
[Inherited from  Buffer]
create a list from this buffer
 => 
String
[Inherited from  Buffer]
the current state of the buffer
as a string.

redefines:

(R 
type
, F 
type
: Typed_Function R, f F)
 => 
R
[Inherited from  Any]
dynamic_apply -- apply `f.call` to `Any.this`'s dynamic type and value

This can be used to perform operation on values depending on their dynamic
type.

Here is an example that takes a `Sequence Any` that may contain boxed values
of types `i32` and `f64`. We can now write a feature `get_f64` that extracts
these values converted to `f64` and build a function `sum` that sums them up
as follows:


NYI: IMPROVEMENT: #5892: If this is fixed, we could write

 => 
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.
(i i64)
 => 
T
[Inherited from  Buffer]
[Abstract feature]
get element at given index i
(i i64, o T)
 => 
unit
[Inherited from  Buffer]
[Abstract feature]
set element at given index i to given value o
 => 
interval i64
[Inherited from  Buffer]
a sequence of all valid indices to access this array. Useful e.g., for
`for`-loops:

 => 
i64
[Inherited from  Buffer]
[Abstract feature]
length of this buffer.
 => 
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 Functions

 => 
String
[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:

 => 
Type
[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
)
 => 
bool
[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.


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


or

 => 
String
[Inherited from  Type]
name of this type, including type parameters, e.g. 'option (list i32)'.
 => 
String
[Inherited from  Type]
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.

NYI: Redefinition allows the type feature to be distinguished from its normal counterpart, see #3913

redefines:

 => 
Type
[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`.
0.095dev (2025-09-09 14:29:31 GIT hash 98644f8f651c2101a0730cfe31c5807993b7603b built by fridi@fzen)