details on function page

Author: critesjosh

docs/docs/aztec/smart_contracts/contract_creation.md

@@ -61,7 +61,7 @@ Aztec makes an important distinction between initialization and public deploymen
 
 ### Initialization
 
-Contract constructors are not enshrined in the protocol, but handled at the application circuit level. Constructors are methods used for initializing a contract, either private or public, and contract classes may declare more than a single constructor. They can be declared by the `#[initializer]` macro. You can read more about how to use them on the [Defining Initializer Functions](../../developers/guides/smart_contracts/initializers.md) page.
+Contract constructors are not enshrined in the protocol, but handled at the application circuit level. Constructors are methods used for initializing a contract, either private or public, and contract classes may declare more than a single constructor. They can be declared by the `#[initializer]` macro. You can read more about how to use them on the [Defining Initializer Functions](../../developers/guides/smart_contracts/define_functions.md#initializer-functions) page.
 
 A contract must ensure:
 

docs/docs/aztec/smart_contracts/functions/index.md

@@ -24,7 +24,7 @@ There are also special oracle functions, which can get data from outside of the
 ## Learn more about functions
 
 - [How function visibility works in Aztec](./visibility.md)
-- How to write an [initializer function](../../../developers/guides/smart_contracts/initializers.md)
+- How to write an [initializer function](../../../developers/guides/smart_contracts/define_functions.md#initializer-functions)
 - [Oracles](../oracles/index.md) and how Aztec smart contracts might use them
 - [How functions work under the hood](./attributes.md)
 

docs/docs/developers/guides/smart_contracts/call_contracts.md

@@ -1,6 +1,6 @@
 ---
 title: Contract Composability
-sidebar_position: 6
+sidebar_position: 5
 tags: [functions, contracts, composability]
 description: Learn how to call other contracts from your Aztec smart contracts.
 ---

docs/docs/developers/guides/smart_contracts/define_functions.md

@@ -5,8 +5,65 @@ tags: [functions, smart-contracts]
 description: Learn how to define functions in your Aztec smart contracts.
 ---
 
-## Overview
+There are several types of functions in Aztec contracts that correspond the the different execution environments in which they run. These include:
+
+- private functions
+- public functions
+- utility functions
+- view functions
+- contract library methods
+- initializer functions
+
+## Examples
+
+### Private Functions
+
+Private functions execute client-side on user devices to maintain private of user inputs and execution. Specify a private function in your contract using the `#[private]` function annotation.
+
+#include_code withdraw noir-projects/noir-contracts/contracts/app/escrow_contract/src/main.nr rust
+
+### Public Functions
+
+<!-- TODO: flesh out with info about all types -->
+
+### Initializer Functions
+
+Initializers are regular functions that set an "initialized" flag (a nullifier) for the contract. A contract can only be initialized once, and contract functions can only be called after the contract has been initialized, much like a constructor. However, if a contract defines no initializers, it can be called at any time. Additionally, you can define as many initializer functions in a contract as you want, both private and public.
+
+#### Annotate with `#[initializer]`
+
+Define your initializer like so:
+
+```rust
+#[initializer]
+fn constructor(){
+    // function logic here
+}
+```
+
+Aztec supports both public and private initializers. Use the appropriate macro, for example for a private initializer:
+
+```rust
+#[private]
+#[initializer]
+fn constructor(){
+    // function logic here
+}
+```
+
+Initializers are commonly used to set an admin, such as this example:
+
+#include_code constructor /noir-projects/noir-contracts/contracts/app/token_contract/src/main.nr rust
+
+Here, the initializer is writing to storage. It can also call another function. Learn more about calling functions from functions [here](./call_contracts.md).
+
+## Multiple initializers
+
+You can set multiple functions as an initializer function simply by annotating each of them with `#[initializer]`. You can then decide which one to call when you are deploying the contract.
+
+Calling any one of the functions annotated with `#[initializer]` will mark the contract as initialized.
+
+To see an initializer in action, follow the [Counter codealong tutorial](../../tutorials/codealong/contract_tutorials/counter_contract.md).
 
-## Example
 
 ## Further Reading

docs/docs/developers/guides/smart_contracts/how_to_prove_history.md

@@ -1,6 +1,6 @@
 ---
 title: Prove Historic State
-sidebar_position: 6
+sidebar_position: 7
 tags: [contracts]
 description: Learn how to prove historical state transitions in your Aztec smart contracts.
 ---

docs/docs/developers/guides/smart_contracts/initializers.md

@@ -20,6 +20,8 @@ A note type can be defined with the macro `#[note]` used on a struct:
 
 #include_code state_vars-CardNote noir-projects/noir-contracts/contracts/docs/docs_example_contract/src/types/card_note.nr rust
 
+<!-- TODO: Explain what #[derive(Eq, Serialize, Deserialize, Packable)] are in the code block -->
+
 In this example, we are implementing a card note that holds a number of `points` as `u8`.
 
 `randomness` is not enforced by the protocol and should be implemented by the application developer. If you do not include `randomness`, and the note preimage can be guessed by an attacker, it makes the note vulnerable to preimage attacks.
@@ -47,21 +49,21 @@ This is the AddressNote:
 
 #include_code address_note_def noir-projects/aztec-nr/address-note/src/address_note.nr rust
 
-### Importing AddressNote
+#### Importing AddressNote
 
-#### In Nargo.toml
+##### In Nargo.toml
 
 ```toml
 address_note = { git="https://github.com/AztecProtocol/aztec-packages/", tag="#include_aztec_version", directory="noir-projects/aztec-nr/address-note" }
 ```
 
-#### In your contract
+##### In your contract
 
 #include_code addressnote_import noir-projects/noir-contracts/contracts/app/escrow_contract/src/main.nr rust
 
-### Working with AddressNote
+#### Working with AddressNote
 
-#### Creating a new note
+##### Creating a new note
 
 Creating a new `AddressNote` takes the following args:
 
@@ -78,21 +80,21 @@ This is the ValueNote struct:
 
 #include_code value-note-def noir-projects/aztec-nr/value-note/src/value_note.nr rust
 
-### Importing ValueNote
+#### Importing ValueNote
 
-#### In Nargo.toml
+##### In Nargo.toml
 
 ```toml
 value_note = { git="https://github.com/AztecProtocol/aztec-packages/", tag="#include_aztec_version", directory="noir-projects/aztec-nr/value-note" }
 ```
 
-#### In your contract
+##### In your contract
 
 #include_code import_valuenote noir-projects/noir-contracts/contracts/test/child_contract/src/main.nr rust
 
-### Working with ValueNote
+#### Working with ValueNote
 
-#### Creating a new note
+##### Creating a new note
 
 Creating a new `ValueNote` takes the following args:
 
@@ -101,7 +103,7 @@ Creating a new `ValueNote` takes the following args:
 
 #include_code valuenote_new noir-projects/noir-contracts/contracts/test/child_contract/src/main.nr rust
 
-#### Getting a balance
+##### Getting a balance
 
 A user may have multiple notes in a set that all refer to the same content (e.g. a set of notes representing a single token balance). By using the `ValueNote` type to represent token balances, you do not have to manually add each of these notes and can instead use a helper function `get_balance()`.
 
@@ -111,7 +113,7 @@ It takes one argument - the set of notes.
 
 This can only be used in an unconstrained function.
 
-#### Incrementing and decrementing
+##### Incrementing and decrementing
 
 Both `increment` and `decrement` functions take the same args:
 

docs/docs/developers/guides/smart_contracts/note_types.md

@@ -202,7 +202,7 @@ Follow the account contract tutorial on the [next page](./write_accounts_contrac
 
 ### Optional: Learn more about concepts mentioned here
 
-- [Initializer functions](../../../guides/smart_contracts/initializers.md)
+- [Initializer functions](../../../guides/smart_contracts/define_functions.md#initializer-functions)
 - [Versions and Updating](../../../guides/local_env/sandbox.md#updating).
 - [Authorizing actions](../../../../aztec/concepts/advanced/authwit.md)
 - [Public logs](../../../guides/smart_contracts/how_to_emit_event.md)

docs/docs/developers/tutorials/contract_tutorials/crowdfunding_contract.md

@@ -29,6 +29,7 @@ pub contract Escrow {
         storage.owner.initialize(note).emit(encode_and_encrypt_note(&mut context, owner));
     }
 
+    // docs:start:withdraw
     // Withdraws balance. Requires that msg.sender is the owner.
     #[private]
     fn withdraw(token: AztecAddress, amount: u128, recipient: AztecAddress) {
@@ -40,4 +41,5 @@ pub contract Escrow {
         Token::at(token).transfer(recipient, amount).call(&mut context);
         // docs:end:call_function
     }
+    // docs:end:withdraw
 }