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diff --git a/docs/guide/functions.md b/docs/guide/functions.md deleted file mode 100644 index 917b8d4..0000000 --- a/docs/guide/functions.md +++ /dev/null @@ -1,54 +0,0 @@ -Another builtin that creates a nested scope is [fn][], which is used to -create a *user-defined function*, which can be used to simplify repetitive -code, amongst other things: - - (import* math) - - (def add-and-trace - (fn - (a b) - (trace (+ a b)))) - - (add-and-trace 1 2) - (add-and-trace 3 4) - -Here a *function* `add-and-trace` is defined. When defining a function, first -the names of the parameters have to be given. The function defined here takes -two parameters, `a` and `b`. The last part of the function definition is called -the *function body*. - -A function created using [fn][] can be called just like an operator. When a -function is called, the parameters to the function are defined with the names -given in the definition, and then the function body is executed. The previous -example is equivalent to the following: - - (import* math) - - (def add-and-trace - (fn - (a b) - (trace (+ a b))) - - (do - (let a 1 - b 2) - (trace (+ a b))) - - (do - (let a 3 - b 4) - (trace (+ a b))) - -and the output of both is: - - trace (+ a b): <num= 3> - trace (+ a b): <num= 7> - -In `alv`, functions are first-class values and can be passed around just like -numbers, strings, etc. However it is very common to define a function with a -name, so there is the `defn` shorthand, which combines the `def` and `fn` -builtins into a single expression. Compare this equivalent definition of the -`add-and-trace` function: - - (defn add-and-trace (a b) - (trace (+ a b))) |
