A collection of utilities for working with the Koto runtime.
Tuple
Provides access to the arguments that were passed into the script when running
the koto
CLI application.
If no arguments were provided then the list is empty.
# Assuming that the script was run with `koto script.koto -- 1 2 "hello"`
size koto.args
# 3
koto.args.first()
# 1
koto.args.last()
# hello
|value: Any| -> Any
Makes a copy of the provided value.
For values that have shared mutable data (i.e., List
, Map
), unique copies of
the data will be made. Note that this only applies to the first level of data,
so nested containers will still share their data with their counterparts in the
original data. To make a copy where any nested containers are also unique,
use koto.deep_copy
.
Copied iterators share the same underlying data as the original, but have a unique iteration position, which is part of an iterator's shared state by default.
If the iterator is a generator, some effort will be made to make the generator's copy produce the same output as the original. However, this isn't guaranteed to be successful. Specifically, the value stack of the copied virtual machine will be scanned for iterators, and each iterator will have a copy made. Iterators that may be used in other ways by the generator (such as being stored in containers or function captures) won't be copied and will still have shared state.
# Copying a map
x = {foo: -1, bar: 99}
y = x
y.foo = 42
x.foo
# -> 42
z = koto.copy x
z.bar = -1
x.bar # x.bar remains unmodified due to the copy
# -> 99
# Copying a list
x = (1..=10).iter()
y = x # y shares the same iteration position as x.
z = koto.copy x # z shares the same iteration data (the range 1..=10),
# but has a unique iteration position.
x.next().get()
# -> 1
x.next().get()
# -> 2
y.next().get() # y shares x's iteration position.
# -> 3
z.next().get() # z isn't impacted by the advancing of x and y.
# -> 1
|value: Any| -> Any
Makes a unique deep copy of the value's data.
This makes a unique copy of the value's data, and then recursively makes deep copies of any nested containers in the value.
If only the first level of data needs to be made unique, then use
koto.copy
.
x = [[1, 2], [3, [4, 5]]]
y = koto.deep_copy x
y[1][1] = 99
x # a deep copy has been made, so x is unaffected by the assignment to y
# -> [[1, 2], [3, [4, 5]]]
|| -> Map
Returns the current module's export
map.
Although typically module items are exported with export
expressions,
it can be useful to export items programatically.
|value: Any| -> Number or Null
Returns the value's hash as an integer, or Null if the value is not hashable.
from koto import hash
(hash 'hi') == (hash 'bye')
# -> false
# Lists aren't hashable
hash [1, 2]
# -> null
# Tuples are hashable if they only contain hashable values
(hash (1, 2)) == null
# -> false
|script: String| -> Chunk
Compiles the provided Koto script
and returns a compiled Chunk
.
Any compilation errors get thrown.
chunk = koto.load '1 + 2'
koto.run chunk
# -> 3
|script: String| -> Any
Compiles and runs the provided Koto script
, and returns the resulting value.
Any compilation or runtime errors get thrown.
|Chunk| -> Any
Runs the compiled Chunk
, and returns the resulting value.
Any runtime errors encountered during execution get thrown.
koto.run '[1, 2, 3, 4].sum()'
# -> 10
String or Null
If a script is being executed then script_dir
provides the directory that the
current script is contained in as a String, otherwise script_dir
is Null.
String or Null
If a script is being executed then script_path
provides the path of the
current script as a String, otherwise script_path
is Null.
|value: Any| -> Number
Returns the size of a value.
The size of a value is typically defined as the number of elements in a container, with some notable exceptions:
range.end() - range.start()
.range.end() + 1 - range.start()
.from koto import size
(size [1, 2, 3]), (size (,))
# -> (3, 0)
(size 'hello'), (size 'héllø'), (size '')
# -> (5, 7, 0)
(size 10..20), (size 10..=20), (size 20..0)
# -> (10, 11, 20)
|value: Any| -> String
Returns the type of the input value as a String.
koto.type true
# -> Bool
x = 42
koto.type x
# -> Number
foo =
@type: "Foo"
koto.type foo
# -> Foo