Feat events (#46)

* feat(if-else): add if-else access control

* fix(if_else): CI issue

* fix: add pr review changes

* fix: pr review comments

* docs: add documentation to contract

* docs(src): add readme file

* docs(src): add contract desc

* fix: terminology & add to SUMMARY

* feat(events): add events

* chore: add to summary

* chore: add type

* fix: pr review changes

---------

Co-authored-by: msaug <msaug@protonmail.com>

listings/ch00-introduction/events/.gitignore

@@ -0,0 +1 @@
+target

listings/ch00-introduction/events/Scarb.toml

@@ -0,0 +1,8 @@
+[package]
+name = "counter"
+version = "0.1.0"
+
+[dependencies]
+starknet = "1.1.0"
+
+[[target.starknet-contract]]

listings/ch00-introduction/events/src/counter.cairo

@@ -0,0 +1,23 @@
+#[contract]
+mod SimpleCounter {
+ struct Storage {
+ // Counter value
+ _counter: u256,
+ }
+
+ #[event]
+ // Increment event - emitted when the counter is incremented.
+ fn Increment(counterVal: u256) {}
+
+ #[constructor]
+ fn constructor() {}
+
+ #[external]
+ fn increment() {
+ let mut counter: u256 = _counter::read();
+ counter += 1;
+ _counter::write(counter);
+ // Emit event
+ Increment(counter);
+ }
+}

listings/ch00-introduction/events/src/lib.cairo

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+mod counter;

src/SUMMARY.md

@@ -12,6 +12,7 @@ Summary
  - [Constructors](./ch00-07-constructor.md)
  - [Function Attributes](./ch00-08-function_attributes.md)
  - [If statements](./ch00-09-if_statements.md)
+ - [Events](./ch00-10-events.md)
 
 - [Applications](./ch01-00-applications.md)
  - [Upgradeable Contract](./ch01-01-upgradeable_contract.md)

src/ch00-10-events.md

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+# Events
+
+An event is defined as function with the #[event] attribute. The parameters of the function correspond to data that will be emitted. An event is to be logged for easy and fast access to querying the data at a later time.
+
+Here's a simple example of a contract using events that emit an event each time a counter is incremented by the "increment" function:
+
+```rust
+{{#include ../listings/ch00-introduction/events/src/counter.cairo}}
+```