constantly
Use constantly to lazily ignore the specified ignore arguments and return the specified vale.
Basic syntax
To lazily ignore arguments and return a value, use the following syntax:
(constantly value ignore1 ignore2 ...)
Arguments
Use the following arguments to specify the value to return and the ignore arguments for the constantly Pact function.
| Argument | Type | Description |
|---|---|---|
value | any | Specifies the value to return. |
ignore1, ignore2, ... | any | Specifies the arguments to ignore. You can have multiple ignore arguments (optional). |
Return value
The constantly function returns the specified value, ignoring any additional arguments.
Examples
The following example demonstrates the constantly function in the Pact REPL:
pact> (filter (constantly true) [1 2 3])
[1 2 3]
In this example, constantly true is used as the predicate function for the filter function.
The constantly function always returns true and ignores the elements of the [1 2 3] list argument, so the filter function always returns the entire list.
The following example illustrate specifying multiple arguments and argument using different data types:
pact> (constantly "hello" {"name": "Kris", "age": 45})
"hello"
pact> (constantly "world" 6 "ignore" "these" "arguments" [2.1 3.0])
"world"
pact> (constantly 42 "ignore" 123 "arguments")
42