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path

path

:
orderable,hashable
 is
[Private constructor]
a feature denoting a path/file in the filesystem

instantiate via path.of, e.g.


or
path.of ["some", "path"] true

Fields

is_absolute
 bool

Functions

 => 
String
[Redefinition of  Any.as_string]
String representation of this path

e.g. "/folder/file" or "relative_folder/file"

redefines:

Full file name or name of the last directory
does this path contain other
(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: ENHANCEMENT: #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.
does this path end with other
is this a relative path representing "current directory"
is this a relative path representing "parent directory"
is this a relative path
is this the root
is this a path with just one segment, i.e. not containing a path separator when normalized
get the parent of this path

if folder is root folder or .
nil is returned
go up n levels, i.e. call parent n times
 => 
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.
relativize path `p` based on this path.

e.g. "/tmp/folder".relative "/tmp/folder/file" will return "file"
resolve o in this path

e.g.


effectively returns


resolving an absolute path returns that path unmodified
the number of segments in this path
checks if this path starts with path `p`

both this and path p must either be absolute or relative
for this to return true.

e.g. (path.of "/tmp/file").starts_with (path.of "/tmp") = true
consider this to represent a file
and return just name of the file
without its extension and path.
(from i32)
 => 
path
get subpath starting from (inclusive)

e.g.
path.of "/tmp/folder/file" .subpath 1 = path.of "folder/file"
(from i32, to i32)
 => 
path
get subpath from (inclusive) to (exclusive)

e.g.
path.of "/tmp/folder/file" .subpath 0 2 = path.of "/tmp/folder"
consider this to represent a file
and return the suffix of the file_name

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:

the current directory path "."
 => 
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:

(a property.orderable.this.type, b property.orderable.this.type)
 => 
bool
[Inherited from  orderable]
equality implements the default equality relation for values of this type.

This relation must be

- reflexive (equality a a),
- symmetric (equality a b = equality b a), and
- transitive ((equality a b && equality b c) : equality a c).

result is true iff 'a' is considered to represent the same abstract value
as 'b'.
create hash code for this instance

This should satisfy the following condition:

(T.equality a b) : (T.hash_code a = T.hash_code b)
(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

define order for paths
 => 
String
[Inherited from  Type]
name of this type, including type parameters, e.g. 'option (list i32)'.
instantiates a path via a given String
if paths starts with / it is considered to be
absolute rather than relative.
(seq Sequence String, is_absolute bool)
 => 
path
instantiates a path

e.g.

the parent directory path ".."
 => 
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:

the root path "/"
the path separator that is used
on the current platform
 => 
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`.

Applicable universe features

These are features in universe, that have an argument with a type constraint that matches this features type and can therefore be used with it.
(T 
type
:
property.equatable, a T, b T)
 => 
bool
equals -- feature that compares two values using the equality relation
defined in their type
(T 
type
:
property.hashable, a T)
 => 
u64
hash of a value
(T 
type
:
property.equatable, a T, b T)
 => 
bool
infix = -- infix operation as shorthand for 'equals'
(T 
type
:
property.orderable, a T, b T)
 => 
bool
does this come strictly before other?
infix <= -- infix operation as shorthand for 'lteq'
(T 
type
:
property.orderable, a T, b T)
 => 
order
three-way comparison between this and other.

result is < 0 if this < other
result is > 0 if this > other
result is = 0 if this = other
(T 
type
:
property.equatable, a T, b T)
 => 
bool
infix = -- infix operation as shorthand for 'equals'
(T 
type
:
property.orderable, a T, b T)
 => 
bool
does this come strictly after other?
(T 
type
:
property.orderable, a T, b T)
 => 
bool
does this come after other?
is `a` contained in `Set` `s`?

This should usually be called using type inference as in

is `a` not contained in `Set` `s`?

This should usually be called using type inference as in

(T 
type
:
property.equatable, a T, b T)
 => 
bool
infix ≟ -- infix operation as shorthand for 'equals'
infix ≤ -- infix operation as shorthand for 'lteq'
(T 
type
:
property.orderable, a T, b T)
 => 
bool
does this come after other?
(T 
type
:
property.orderable, a T, b T)
 => 
order
three-way comparison between this and other.

result is < 0 if this < other
result is > 0 if this > other
result is = 0 if this = other
(T 
type
:
property.orderable, a T, b T)
 => 
bool
does this come strictly before other?
(T 
type
:
property.orderable, a T, b T)
 => 
bool
does this come strictly after other?
(T 
type
:
property.partially_orderable, a T, b T)
 => 
bool
lteq -- feature that compares two values using the lteq relation
defined in their type
(T 
type
:
property.orderable, a T, b T)
 => 
T
maximum of two values
memoize `f`.
wraps f so that f will only be called once for every unique input.

The term "memoization" was coined by Donald Michie in 1968 and
is derived from the Latin word "memorandum" ("to be remembered"),
usually truncated as "memo" in American English, and thus carries
the meaning of "turning a function into something to be remembered".
https://en.wikipedia.org/wiki/Memoization

example:

(T 
type
:
property.orderable, a T, b T)
 => 
T
minimum of two values
0.095dev (2026-02-20 12:42:29 GIT hash dbcc3e4b3d2a59f66230b482cff8f0b018178d77 built by fridi@fzen)