From d6845d333bd76d9064fb4a08714a84a8faa1fa8b Mon Sep 17 00:00:00 2001
From: Nick Van Doorn <vandoorn.nick@gmail.com>
Date: Sun, 19 Aug 2018 21:55:44 -0700
Subject: Implement initial readme

---
 readme.md | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/readme.md b/readme.md
index e69de29..4f2d5ef 100644
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+# funCtional
+
+Generic functional programming in C with support for statically allocated memory. You should probably use a `for` loop but this is fun!
+
+## Usage
+
+### Setup
+
+To get started, pack your `Functional` struct with the required pointers and callbacks:
+
+```C
+Functional f = {
+    .args = {.i = 0,
+             .n = 3,
+             .arr = (void*)people,
+             .ctxp = (void*)"Harry",
+             .storage = filteredPeople},
+    .filter = shouldIncludePerson,
+    .map = copyPerson,
+    .derefInput = derefPerson,
+};
+```
+
+#### f.filter
+
+Called to determine if `f.args.arr[f.args.i]` should be included in the filtered collection (for `func_filter` or `func_find`). The caller is responsible for copying filtered items using `f.map` when calling `func_filter`.
+
+#### f.map
+
+Called to copy or transform `f.args.arr[f.args.i]`. This callback is required for `func_filter` and `func_map`, however when used with `func_filter`, it's only responsibility should be copying.
+
+### f.derefInput
+
+Required by `func_find` to dereference the correct element of `f.args.arr`.
+
+#### f.args.arr
+
+A `void*` pointer to the first element of the array to be iterated over.
+
+#### f.args.storage
+
+A `void*` pointer to the first element of the storage array where mapped and filtered elements will be copied.
+
+#### f.args.i
+
+Iteration index used to iterate over `args.arr` where `args.i < args.n`.
+
+#### f.args.n
+
+Total length of `arg.arr`. After running, this will be changed to the length of `args.storage`
+
+### f.args.offset
+
+When filtering, `args.i` increments to cover all of `args.arr`, but `arr.storage` may contain fewer items. Therefore, the callback responsible for copying when filtering (`f.map`) may need to account for this difference (see `example.c`).
+
+#### f.args.ctxp
+
+Context pointer that is freely available for user use.
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