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-rw-r--r--LICENSE.txt359
-rw-r--r--bf.html.markdown8
-rw-r--r--cairo.html.markdown864
-rw-r--r--de-de/yaml-de.html.markdown2
-rw-r--r--hjson.html.markdown2
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-rw-r--r--images/cairo/connect2.pngbin0 -> 66962 bytes
-rw-r--r--images/cairo/declare.pngbin0 -> 74011 bytes
-rw-r--r--images/cairo/deploy.pngbin0 -> 99481 bytes
-rw-r--r--lbstanza.html.markdown6
-rw-r--r--mips.html.markdown6
-rw-r--r--openscad.html.markdown2
-rw-r--r--python.html.markdown4
-rw-r--r--r.html.markdown2
-rw-r--r--raku.html.markdown2
-rw-r--r--rust.html.markdown2
-rw-r--r--set-theory.html.markdown2
-rw-r--r--zh-cn/clojure-macro-cn.html.markdown2
-rw-r--r--zig.html.markdown52
20 files changed, 1273 insertions, 42 deletions
diff --git a/LICENSE.txt b/LICENSE.txt
new file mode 100644
index 00000000..604209a8
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,359 @@
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diff --git a/bf.html.markdown b/bf.html.markdown
index 5ede0546..adc58f02 100644
--- a/bf.html.markdown
+++ b/bf.html.markdown
@@ -4,12 +4,13 @@ filename: bf.bf
contributors:
- ["Prajit Ramachandran", "http://prajitr.github.io/"]
- ["Mathias Bynens", "http://mathiasbynens.be/"]
+ - ["rilysh", "https://github.com/rilysh"]
---
Brainfuck (not capitalized except at the start of a sentence) is an extremely
minimal Turing-complete programming language with just 8 commands.
-You can try brainfuck on your browser with [brainfuck-visualizer](https://brainfuck-visualizer.herokuapp.com).
+You can try brainfuck on your browser with [brainfuck-online](https://copy.sh/brainfuck/).
```bf
Any character not "><+-.,[]" (excluding quotation marks) is ignored.
@@ -80,3 +81,8 @@ And that's brainfuck. Not that hard, eh? For fun, you can write your own
brainfuck programs, or you can write a brainfuck interpreter in another
language. The interpreter is fairly simple to implement, but if you're a
masochist, try writing a brainfuck interpreter… in brainfuck.
+
+## Further Reading
+ * [esolang-wiki](https://esolangs.org/wiki/Brainfuck)
+ * [learn brainfuck](http://cydathria.com/bf/brainfuck.html)
+ * [other resources](http://www.muppetlabs.com/~breadbox/bf/)
diff --git a/cairo.html.markdown b/cairo.html.markdown
new file mode 100644
index 00000000..dd3ca036
--- /dev/null
+++ b/cairo.html.markdown
@@ -0,0 +1,864 @@
+---
+language: Cairo
+filename: learnCairo.sol
+contributors:
+ - ["Darlington Nnam", "https://github.com/Darlington02"]
+---
+
+# Cairo
+
+Cairo is a Turing-complete language that allows you write provable programs
+(where one party can prove to another that a certain computation was executed
+correctly) on StarkNet.
+
+## StarkNet
+
+StarkNet is a decentralized ZK-rollup that operates as an Ethereum layer 2
+chain.
+
+In this document, we are going to be going in-depth into understanding Cairo's
+syntax and how you could create and deploy a Cairo smart contract on StarkNet.
+
+**NB: As at the time of this writing, StarkNet is still at v0.10.3, with Cairo
+1.0 coming soon. The ecosystem is young and evolving very fast, so you might
+want to check the [official docs](https://www.cairo-lang.org/docs) to confirm
+this document is still up-to-date. Pull requests are welcome!**
+
+## Setting Up A Development Environment
+
+Before we get started writing codes, we will need to setup a Cairo development
+environment, for writing, compiling and deploying our contracts to StarkNet.
+For the purpose of this tutorial we are going to be using the
+[Protostar Framework](https://github.com/software-mansion/protostar).
+Installation steps can be found in the docs
+[here](https://docs.swmansion.com/protostar/docs/tutorials/installation).
+Note that Protostar supports just Mac and Linux OS, Windows users might need to
+use WSL, or go for other alternatives such as the Official
+[StarkNet CLI](https://www.cairo-lang.org/docs/quickstart.html) or
+[Nile from Openzeppelin](https://github.com/OpenZeppelin/nile)
+
+Once you're done with the installations, run the command `protostar -v` to
+confirm your installation was successful. If successful, you should see your
+Protostar version displayed on the screen.
+
+## Initializing a new project
+
+Protostar similar to Truffle for solidity development can be installed once and
+used for multiple projects. To initialize a new Protostar project, run the
+following command:
+
+```
+protostar init
+```
+
+It would then request the project's name and the library's directory name,
+you'd need to fill in this, and a new project will be initialized successfully.
+
+## Compiling, Declaring, Deploying and Interacting with StarkNet Contracts
+
+Within the `src` folder you'll find a boilerplate contract that comes with
+initializing a new Protostar project, `main.cairo`. We are going to be
+compiling, declaring and deploying this contract.
+
+### Compiling Contracts
+
+To compile a Cairo contract using Protostar, ensure a path to the contract is
+specified in the `[contracts]` section of the `protostar.toml` file. Once
+you've done that, open your terminal and run the command:
+
+```
+protostar build
+```
+
+And you should get an output similar to what you see below, with a `main.json`
+and `main_abi.json` files created in the `build` folder.
+<img src="./images/cairo/build.png" alt="building your contract">
+
+### Declaring Contracts
+
+With the recent StarkNet update to 0.10.3, the DEPLOY transaction was
+deprecated and no longer works. To deploy a transaction, you must first declare
+a Contract to obtain the class hash, then deploy the declared contract using the
+[Universal Deployer Contract](https://community.starknet.io/t/universal-deployer-contract-proposal/1864).
+
+Before declaring or deploying your contract using Protostar, you should set the
+private key associated with the specified account address in a file, or in the
+terminal. To set your private key in the terminal, run the command:
+
+```
+export PROTOSTAR_ACCOUNT_PRIVATE_KEY=[YOUR PRIVATE KEY HERE]
+```
+
+Then to declare our contract using Protostar run the following command (for
+visual clarity, the backslash sign symbolizes the continuing line):
+
+```
+protostar declare ./build/main.json \
+ --network testnet \
+ --account 0x0691622bBFD29e835bA4004e7425A4e9630840EbD11c5269DE51C16774585b16 \
+ --max-fee auto
+```
+
+where `network` specifies the network we are deploying to, `account` specifies
+account whose private key we are using, `max-fee` specifies the maximum fee to
+be paid for the transaction. You should get the class hash outputted as seen
+below:
+<img src="./images/cairo/declare.png" alt="declaring your contract">
+
+### Deploying Contracts
+
+After obtaining our class hash from declaring, we can now deploy using the
+command below:
+
+```
+protostar \
+ deploy 0x02a5de1b145e18dfeb31c7cd7ff403714ededf5f3fdf75f8b0ac96f2017541bc \
+ --network testnet \
+ --account 0x0691622bBFD29e835bA4004e7425A4e9630840EbD11c5269DE51C16774585b16 \
+ --max-fee auto
+```
+
+where `0x02a5de1b145e18dfeb31c7cd7ff403714ededf5f3fdf75f8b0ac96f2017541bc` is
+the class hash of our contract.
+<img src="./images/cairo/deploy.png" alt="deploying your contract">
+
+### Interacting with Contracts
+
+To interact with your deployed contract, we will be using `Argent X`
+(alternative: `Braavos`), and `Starkscan` (alternative: `Voyager`). To install
+and setup `Argent X`, see this
+[guide](https://www.argent.xyz/learn/how-to-create-an-argent-x-wallet/).
+
+Copy your contract address, displayed on screen from the previous step, and
+head over to [Starkscan](https://testnet.starkscan.co/) to search for the
+contract. Once found, you can make write calls to the contract in the following
+sequence:
+
++ click on the "connect wallet" button,
+ <img src="./images/cairo/connect.png" alt="connect wallet">
++ select `Argent X` and approve the connection
+ <img src="./images/cairo/connect2.png" alt="connect to argentX">
++ you can now make read and write calls easily.
+
+## Let's learn Cairo
+
+First let's look at a default contract that comes with Protostar which allows
+you to set balance on deployment, increase, and get the balance.
+
+```
+// Language directive - instructs compiler its a StarkNet contract
+%lang starknet
+
+// Library imports from the Cairo-lang library
+from starkware.cairo.common.math import assert_nn
+from starkware.cairo.common.cairo_builtins import HashBuiltin
+
+// @dev Storage variable that stores the balance of a user.
+// @storage_var is a decorator that instructs the compiler the function
+// below it is a storage variable.
+@storage_var
+func balance() -> (res: felt) {}
+
+// @dev Constructor writes the balance variable to 0 on deployment
+// Constructors sets storage variables on deployment. Can accept arguments too.
+@constructor
+func constructor{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}() {
+ balance.write(0);
+ return();
+}
+
+// @dev increase_balance updates the balance variable
+// @param amount the amount you want to add to balance
+// @external is a decorator that specifies the func below it is an external
+// function.
+@external
+func increase_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(amount: felt){
+ with_attr error_message("Amount must be positive. Got: {amount}.") {
+ assert_nn(amount);
+ }
+
+ let (res) = balance.read();
+ balance.write(res + amount);
+ return ();
+}
+
+// @dev returns the balance variable
+// @view is a decorator that specifies the func below it is a view function.
+@view
+func get_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}() -> (res: felt) {
+ let (res) = balance.read();
+ return (res,);
+}
+```
+
+Before proceeding to the main lessons, try to build, deploy and interact with
+this contract.
+NB: You should be at `main.cairo` if you are using Protostar.
+
+### 1. The Felt data type
+
+Unlike solidity, where you have access to various data types, Cairo comes with
+just a single data type `..felts`. Felts stands for Field elements, and are a
+252 bit integer in the range `0<=x<=P` where `P` is a prime number. You can
+create a `Uint256` in Cairo by utlizing a struct of two 128 bits felts.
+
+```
+struct Uint256 {
+ low: felt, // The low 128 bits of the value.
+ high: felt, // The high 128 bits of the value.
+}
+```
+
+To avoid running into issues with divisions, it's safer to work with the
+`unsigned_div_rem` method from Cairo-lang's library.
+
+### 2. Lang Directive and Imports
+
+To get started with writing a StarkNet contract, you must specify the directive:
+
+```
+%lang starknet
+```
+
+This directive informs the compiler you are writing a contract and not a
+program. The difference between both is contracts have access to StarkNet's
+storage, programs don't and as such are stateless.
+
+There are important functions you might need to import from the official
+Cairo-lang library or Openzeppelin's, e.g.
+
+```
+from starkware.cairo.common.cairo_builtins import HashBuiltin
+from cairo_contracts.src.openzeppelin.token.erc20.library import ERC20
+from starkware.cairo.common.uint256 import Uint256
+from starkware.cairo.common.bool import TRUE
+```
+
+### 3. Data Structures
+
++ Storage variables: Cairo's storage is a map with `2^251` slots, where each
+ slot is a felt which is initialized to `0`. You create one using the
+ `@storage_var` decorator.
+
+ ```
+ @storage_var
+ func names() -> (name: felt) {}
+ ```
+
++ Storage mappings: Unlike Solidity where mappings have a separate keyword, in
+ Cairo you create mappings using storage variables.
+
+ ```
+ @storage_var
+ func names(address: felt) -> (name: felt) {}
+ ```
+
++ Structs: are a means to create custom data types in Cairo. A `struct` has a
+ size, which is the sum of the sizes of its members. The size can be
+ retrieved using `MyStruct.SIZE`. You create a struct in Cairo using the
+ `struct` keyword.
+
+ ```
+ struct Person {
+ name: felt,
+ age: felt,
+ address: felt,
+ }
+ ```
+
++ Constants: Constants are fixed and as such can't be altered after being set.
+ They evaluate to an integer (field element) at compile time. To create a
+ constant in Cairo, you use the `const` keyword. It's proper practice to
+ capitalize constant names.
+
+ ```
+ const USER = 0x01C6cfC1DB2ae90dACEA243F0a8C2F4e32560F7cDD398e4dA2Cc56B733774E9b
+ ```
+
++ Arrays: Arrays can be defined as a `pointer(felt*)` to the first element of
+ the array. As an array is populated, its elements take up contigous memory
+ cells. The `alloc` keyword can be used to dynamically allocate a new memory
+ segment, which can be used to store an array:
+
+ ```
+ let (myArray: felt*) = alloc ();
+ assert myArray[0] = 1;
+ assert myArray[1] = 2;
+ assert myArray[3] = 3;
+ ```
+
+ You can also use the `new` operator to create fixed-size arrays using
+ tuples. The new operator is useful as it enables you allocate memory and
+ initialize the object in one instruction
+
+ ```
+ func foo() {
+ tempvar arr: felt* = new (1, 1, 2, 3, 5);
+ assert arr[4] = 5;
+ return ();
+ }
+ ```
+
++ Tuples: A tuple is a finite, ordered, unchangeable list of elements. It is
+ represented as a comma-separated list of elements enclosed by parentheses.
+ Their elements may be of any combination of valid types.
+
+ ```
+ local tuple0: (felt, felt, felt) = (7, 9, 13);
+ ```
+
++ Events: Events allows a contract emit information during the course of its
+ execution, that can be used outside of StarkNet. An event can be created,
+ subsequently emitted:
+
+ ```
+ @event
+ func name_stored(address, name) {}
+
+ name_stored.emit(address, name);
+ ```
+
+### 4. Constructors, External and View functions
+
++ Constructors: Constructors are a way to intialize state variables on
+ contract deployment. You create a constructor using the `@constructor`
+ decorator.
+
+ ```
+ @constructor
+ func constructor{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+ range_check_ptr}(_name: felt) {
+ let (caller) = get_caller_address();
+ names.write(caller, _name);
+ return ();
+ }
+ ```
+
++ External functions: External functions are functions that modifies the state
+ of the network. You create an external function using the `@external`
+ decorator:
+
+ ```
+ @external
+ func store_name{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+ range_check_ptr}(_name: felt){
+ let (caller) = get_caller_address();
+ names.write(caller, _name);
+ stored_name.emit(caller, _name);
+ return ();
+ }
+ ```
+
++ View functions: View functions do not modify the state of the blockchain.
+ You can create a view function using the `@view` decorator.
+
+ ```
+ @view
+ func get_name{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+ range_check_ptr}(_address: felt) -> (name: felt){
+ let (name) = names.read(_address);
+ return (name,);
+ }
+ ```
+
+ NB: Unlike Solidity, Cairo supports just External and View function types.
+ You can alternatively also create an internal function by not adding any
+ decorator to the function.
+
+### 5. Decorators
+
+All functions in Cairo are specified by the `func` keyword, which can be
+confusing. Decorators are used by the compiler to distinguish between these
+functions.
+
+Here are the most common decorators you'll encounter in Cairo:
+
++ `@storage_var` — used for specifying state variables.
++ `@constructor` — used for specifying constructors.
++ `@external` — used for specifying functions that write to a state variable.
++ `@event` — used for specifying events
++ `@view` — used to specify functions reading from a state variable
++ `@contract_interface` — used for specifying function interfaces.
++ `@l1_handler` — used for specifying functions that processes message sent from
+ an L1 contract in a messaging bridge.
+
+### 6. BUILTINS, HINTS & IMPLICIT Arguments
+
++ `BUILTINS` are predefined optimized low-level execution units, which are
+ added to Cairo’s CPU board. They help perform predefined computations like
+ pedersen hashing, bitwise operations etc, which are expensive to perform in
+ Vanilla Cairo. Each builtin in Cairo is assigned a separate memory location,
+ accessible through regular Cairo memory calls using implicit parameters. You
+ specify them using the `%builtins` directive
+
+ Here is a list of available builtins in Cairo:
+
+ + `output` — the output builtin is used for writing program outputs
+ + `pedersen` — the pedersen builtin is used for pedersen hashing
+ computations
+ + `range_check` — This builtin is mostly used for integer comparisons,
+ and facilitates check to confirm that a field element is within a range
+ `[0, 2^128)`
+ + `ecdsa` — the ecdsa builtin is used for verifying ECDSA signatures
+ + `bitwise` — the bitwise builtin is used for carrying out bitwise
+ operations on felts
+
++ `HINTS` are pieces of Python codes, which contains instructions that only
+ the prover sees and executes. From the point of view of the verifier these
+ hints do not exist. To specify a hint in Cairo, you need to encapsulate it
+ within `%{` and `%}`. It is good practice to avoid using hints as much as
+ you can in your contracts, as hints are not added to the bytecode, and thus
+ do not count in the total number of execution steps.
+
+ ```
+ %{
+ # Python hint goes here
+ %}
+ ```
+
++ `IMPLICIT ARGUMENTS` are not restricted to the function body, but can be
+ inherited by other functions calls that require them. Implicit arguments are
+ passed in between curly bracelets, like you can see below:
+
+ ```
+ func store_name{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+ range_check_ptr}(_name: felt){
+ let (caller) = get_caller_address();
+ names.write(caller, _name);
+ stored_name.emit(caller, _name);
+ return ();
+ }
+ ```
+
+### 7. Error Messages and Access Controls
+
+You can create custom errors in Cairo which is outputted to the user upon failed
+execution. This can be very useful for implementing checks and proper access
+control mechanisms. An example is preventing a user to call a function except
+user is `admin`.
+
+```
+// imports
+from starkware.starknet.common.syscalls import get_caller_address
+
+// create an admin constant
+const ADMIN = 0x01C6cfC1DB2ae90dACEA243F0a8C2F4e32560F7cDD398e4dA2Cc56B733774E9b
+
+// implement access control
+with_attr error_message("You do not have access to make this action!"){
+ let (caller) = get_caller_address();
+ assert ADMIN = caller;
+}
+
+// using an assert statement throws if condition is not true, thus
+// returning the specified error.
+```
+
+### 8. Contract Interfaces
+
+Contract interfaces provide a means for one contract to invoke or call the
+external function of another contract. To create a contract interface, you use
+the `@contract_interface` keyword:
+
+```
+@contract_interface
+ namespace IENS {
+ func store_name(_name: felt) {
+ }
+
+ func get_name(_address: felt) -> (name: felt) {
+ }
+ }
+```
+
+Once a contract interface is specified, any contract can make calls to that
+contract passing in the contract address as the first parameter like this:
+
+```
+IENS.store_name(contract_address, _name);
+```
+
+Note that Interfaces exclude the function body/logic and the implicit
+arguments.
+
+### 9. Recursions
+
+Due to the unavailability of loops, Recursion is the go-to for similar
+operations. In simple terms, a recursive function is one which calls itself
+repeatedly.
+
+A good example to demonstrate this is writing a function for getting the nth
+fibonacci number:
+
+```
+@external
+func fibonacci{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(n : felt) -> (result : felt){
+ alloc_locals;
+ if (n == 0){
+ return (0);
+ }
+ if (n == 1){
+ return (1);
+ }
+ let (local x) = fibonacci(n - 1);
+ let (local y) = fibonacci(n - 2);
+ return (result=(x + y));
+}
+```
+
+The nth fibonacci term is the sum of the `nth - 1` and the `nth - 2` numbers,
+that's why we get these two as `(x,y)` using recursion.
+
+NB: when implementing recursive functions, always remember to implement a base
+case (`n==0`, `n==1` in our case), to prevent stack overflows.
+
+### 10. Registers
+
+Registers holds values that may change over time. There are 3 major types of
+registers:
+
++ `ap` (allocation pointer) points to a yet unused memory. Temporary variables
+ created using `let`, `tempvar` are held here, and thus susceptible to being
+ revoked.
++ `fp` (frame pointer) points to the frame of the current function. The address
+ of all the function arguments and local variables are relative to this
+ register and as such can never be revoked.
++ `pc` (program counter) points to the current instruction.
+
+### 11. Revoked References
+
+Revoked references occur when there is a call instruction to another function,
+between the definition of a reference variable that depends on `ap` (temp
+variables) and its usage. This occurs as the compiler may not be able to compute
+the change of `ap` (as one may jump to the label from another place in the
+program, or call a function that might change ap in an unknown way).
+
+Here is an example to demonstrate what I mean:
+
+```
+@external
+func get_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}() -> (res: felt) {
+ return (res=100);
+}
+
+@external
+func double_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}() -> (res: felt) {
+ let multiplier = 2;
+ let (balance) = get_balance();
+ let new_balance = balance * multiplier;
+ return (res=new_balance);
+}
+```
+
+If you run that code, you'll run into the revoked reference error as we are
+trying to access the `multiplier` variable after calling the `get_balance`
+function.
+
+In simple cases you can resolve revoked references by adding the keyword
+`alloc_locals` within function scopes. In more complex cases you might need to
+create a local variable to resolve it.
+
+```
+// resolving the `double_balance` function:
+@external
+func double_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}() -> (res: felt) {
+ alloc_locals;
+ let multiplier = 2;
+ let (balance) = get_balance();
+ let new_balance = balance * multiplier;
+ return (res=new_balance);
+}
+```
+
+### 12. Understanding Cairo's Punctuations
+
++ `;` (semicolon). Used at the end of each instruction
++ `()` (parentheses). Used in a function declaration, if statements, and in a
+ tuple declaration
++ `{}` (curly braces). Used in a declaration of implicit arguments and to define
+ code blocks.
++ `[]` (square brackets). Standalone brackets represent the value at a
+ particular address location (such as the allocation pointer, `[ap]`). Brackets
+ following a pointer or a tuple act as a subscript operator, where `x[2]`
+ represents the element with index `2` in `x`.
++ `*` (single asterisk). Refers to the pointer of an expression.
++ `%` (percent sign). Appears at the start of a directive, such as `%builtins`
+ or `%lang`.
++ `%{` and `%}` represent Python hints.
++ `_` (underscore). A placeholder to handle values that are not used, such as an
+ unused function return value.
+
+## Full Contract Example
+
+Below is a simple automated market maker contract example that implements most
+of what we just learnt! Re-write, deploy, have fun!
+
+```
+%lang starknet
+
+from starkware.cairo.common.cairo_builtins import HashBuiltin
+from starkware.cairo.common.hash import hash2
+from starkware.cairo.common.alloc import alloc
+from starkware.cairo.common.math import (assert_le, assert_nn_le,
+ unsigned_div_rem)
+from starkware.starknet.common.syscalls import (get_caller_address,
+ storage_read, storage_write)
+
+
+// CONSTANTS
+//
+// @dev the maximum amount of each token that belongs to the AMM
+const BALANCE_UPPER_BOUND = 2 ** 64;
+
+const TOKEN_TYPE_A = 1;
+const TOKEN_TYPE_B = 2;
+
+// @dev Ensure the user's balances are much smaller than the pool's balance
+const POOL_UPPER_BOUND = 2 ** 30;
+const ACCOUNT_BALANCE_BOUND = 1073741; // (2 ** 30 / 1000)
+
+
+// STORAGE VARIABLES
+//
+// @dev A map from account and token type to corresponding balance
+@storage_var
+func account_balance(account_id: felt, token_type: felt) -> (balance: felt) {}
+
+// @dev a map from token type to corresponding pool balance
+@storage_var
+func pool_balance(token_type: felt) -> (balance: felt) {}
+
+
+// GETTERS
+//
+// @dev returns account balance for a given token
+// @param account_id Account to be queried
+// @param token_type Token to be queried
+@view
+func get_account_token_balance{syscall_ptr: felt*, pedersen_ptr:
+HashBuiltin*, range_check_ptr}(
+ account_id: felt, token_type: felt
+ ) -> (balance: felt) {
+ return account_balance.read(account_id, token_type);
+}
+
+// @dev return the pool's balance
+// @param token_type Token type to get pool balance
+@view
+func get_pool_token_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(
+ token_type: felt
+ ) -> (balance: felt) {
+ return pool_balance.read(token_type);
+}
+
+
+// EXTERNALS
+//
+// @dev set pool balance for a given token
+// @param token_type Token whose balance is to be set
+// @param balance Amount to be set as balance
+@external
+func set_pool_token_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(
+ token_type: felt, balance: felt
+ ) {
+ with_attr error_message("exceeds maximum allowed tokens!"){
+ assert_nn_le(balance, BALANCE_UPPER_BOUND - 1);
+ }
+
+ pool_balance.write(token_type, balance);
+ return ();
+}
+
+// @dev add demo token to the given account
+// @param token_a_amount amount of token a to be added
+// @param token_b_amount amount of token b to be added
+@external
+func add_demo_token{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(
+ token_a_amount: felt, token_b_amount: felt
+ ) {
+ alloc_locals;
+ let (account_id) = get_caller_address();
+
+ modify_account_balance(account_id=account_id, token_type=TOKEN_TYPE_A,
+ amount=token_a_amount);
+ modify_account_balance(account_id=account_id, token_type=TOKEN_TYPE_B,
+ amount=token_b_amount);
+
+ return ();
+}
+
+// @dev intialize AMM
+// @param token_a amount of token a to be set in pool
+// @param token_b amount of token b to be set in pool
+@external
+func init_pool{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(
+ token_a: felt, token_b: felt
+ ) {
+ with_attr error_message("exceeds maximum allowed tokens!"){
+ assert_nn_le(token_a, POOL_UPPER_BOUND - 1);
+ assert_nn_le(token_b, POOL_UPPER_BOUND - 1);
+ }
+
+ set_pool_token_balance(token_type=TOKEN_TYPE_A, balance=token_a);
+ set_pool_token_balance(token_type=TOKEN_TYPE_B, balance=token_b);
+
+ return ();
+}
+
+
+// @dev swaps token between the given account and the pool
+// @param token_from token to be swapped
+// @param amount_from amount of token to be swapped
+// @return amount_to the token swapped to
+@external
+func swap{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*, range_check_ptr}(
+ token_from: felt, amount_from: felt
+ ) -> (amount_to: felt) {
+ alloc_locals;
+ let (account_id) = get_caller_address();
+
+ // verify token_from is TOKEN_TYPE_A or TOKEN_TYPE_B
+ with_attr error_message("token not allowed in pool!"){
+ assert (token_from - TOKEN_TYPE_A) * (token_from - TOKEN_TYPE_B) = 0;
+ }
+
+ // check requested amount_from is valid
+ with_attr error_message("exceeds maximum allowed tokens!"){
+ assert_nn_le(amount_from, BALANCE_UPPER_BOUND - 1);
+ }
+
+ // check user has enough funds
+ let (account_from_balance) =
+ get_account_token_balance(account_id=account_id, token_type=token_from);
+ with_attr error_message("insufficient balance!"){
+ assert_le(amount_from, account_from_balance);
+ }
+
+ let (token_to) = get_opposite_token(token_type=token_from);
+ let (amount_to) = do_swap(account_id=account_id, token_from=token_from,
+ token_to=token_to, amount_from=amount_from);
+
+ return (amount_to=amount_to);
+}
+
+
+// INTERNALS
+//
+// @dev internal function that updates account balance for a given token
+// @param account_id Account whose balance is to be modified
+// @param token_type Token type to be modified
+// @param amount Amount Amount to be added
+func modify_account_balance{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(
+ account_id: felt, token_type: felt, amount: felt
+ ) {
+ let (current_balance) = account_balance.read(account_id, token_type);
+ tempvar new_balance = current_balance + amount;
+
+ with_attr error_message("exceeds maximum allowed tokens!"){
+ assert_nn_le(new_balance, BALANCE_UPPER_BOUND - 1);
+ }
+
+ account_balance.write(account_id=account_id, token_type=token_type,
+ value=new_balance);
+ return ();
+}
+
+// @dev internal function that swaps tokens between the given account and
+// the pool
+// @param account_id Account whose tokens are to be swapped
+// @param token_from Token type to be swapped from
+// @param token_to Token type to be swapped to
+// @param amount_from Amount to be swapped
+func do_swap{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*,
+range_check_ptr}(
+ account_id: felt, token_from: felt, token_to: felt, amount_from: felt
+ ) -> (amount_to: felt) {
+ alloc_locals;
+
+ // get pool balance
+ let (local amm_from_balance) = get_pool_token_balance(token_type =
+ token_from);
+ let (local amm_to_balance) = get_pool_token_balance(token_type=token_to);
+
+ // calculate swap amount
+ let (local amount_to, _) = unsigned_div_rem((amm_to_balance *
+ amount_from), (amm_from_balance + amount_from));
+
+ // update token_from balances
+ modify_account_balance(account_id=account_id, token_type=token_from,
+ amount=-amount_from);
+ set_pool_token_balance(token_type=token_from, balance=(amm_from_balance
+ + amount_from));
+
+ // update token_to balances
+ modify_account_balance(account_id=account_id, token_type=token_to,
+ amount=amount_to);
+ set_pool_token_balance(token_type=token_to, balance=(amm_to_balance -
+ amount_to));
+
+ return (amount_to=amount_to);
+}
+
+
+// @dev internal function to get the opposite token type
+// @param token_type Token whose opposite pair needs to be gotten
+func get_opposite_token(token_type: felt) -> (t: felt) {
+ if(token_type == TOKEN_TYPE_A) {
+ return (t=TOKEN_TYPE_B);
+ } else {
+ return (t=TOKEN_TYPE_A);
+ }
+}
+```
+
+## Additional Resources
+
++ [Official documentation](https://www.cairo-lang.org/docs/)
++ [Starknet EDU](https://medium.com/starknet-edu)
++ [Journey through Cairo](https://medium.com/@darlingtonnnam/journey-through-cairo-i-setting-up-protostar-and-argentx-for-local-development-ba40ae6c5524)
++ [Demystifying Cairo whitepaper](https://medium.com/@pban/demystifying-cairo-white-paper-part-i-b71976ad0108)
++ [Learn about StarkNet with Argent](https://www.argent.xyz/learn/tag/starknet/)
+
+## Development Frameworks
+
++ [Protostar](https://docs.swmansion.com/protostar/docs/tutorials/installation)
++ [Nile](https://github.com/OpenZeppelin/nile)
++ [StarkNet CLI](https://www.cairo-lang.org/docs/quickstart.html)
+
+## Helpful Libraries
+
++ [Cairo-lang](https://github.com/starkware-libs/cairo-lang)
++ [Openzeppelin](https://github.com/OpenZeppelin/cairo-contracts)
+
+## Educational Repos
+
++ [StarkNet Cairo 101](https://github.com/starknet-edu/starknet-cairo-101)
++ [StarkNet ERC721](https://github.com/starknet-edu/starknet-erc721)
++ [StarkNet ERC20](https://github.com/starknet-edu/starknet-erc20)
++ [L1 -> L2 Messaging](https://github.com/starknet-edu/starknet-messaging-bridge)
++ [StarkNet Debug](https://github.com/starknet-edu/starknet-debug)
++ [StarkNet Accounts](https://github.com/starknet-edu/starknet-accounts)
++ [Min-Starknet](https://github.com/Darlington02/min-starknet)
+
+## Security
+
++ [Amarna static analysis for Cairo programs](https://blog.trailofbits.com/2022/04/20/amarna-static-analysis-for-cairo-programs/)
++ [Cairo and StarkNet security by Ctrl03](https://ctrlc03.github.io/)
++ [How to hack almost any Cairo smart contract](https://medium.com/ginger-security/how-to-hack-almost-any-starknet-cairo-smart-contract-67b4681ac0f6)
++ [Analyzing Cairo code using Armana](https://dic0de.substack.com/p/analyzing-cairo-code-using-amarna?sd=pf)
+
+## Future TO-DOs
+
+Update tutorial to fit Cairo 1.0
diff --git a/de-de/yaml-de.html.markdown b/de-de/yaml-de.html.markdown
index 0332c912..00e4fd94 100644
--- a/de-de/yaml-de.html.markdown
+++ b/de-de/yaml-de.html.markdown
@@ -112,7 +112,7 @@ python_komplexe_Zahlen: !!python/komplex 1+2j
####################
# Strings und Zahlen sind nicht die einzigen Skalare, welche YAML versteht.
-# ISO-formatierte Datumsangaben and Zeiangaben können ebenso geparsed werden.
+# ISO-formatierte Datumsangaben and Zeitangaben können ebenso geparsed werden.
DatumZeit: 2001-12-15T02:59:43.1Z
DatumZeit_mit_Leerzeichen: 2001-12-14 21:59:43.10 -5
Datum: 2002-12-14
diff --git a/hjson.html.markdown b/hjson.html.markdown
index b9b35062..6b3cc3ed 100644
--- a/hjson.html.markdown
+++ b/hjson.html.markdown
@@ -15,7 +15,7 @@ to read and edit before passing the JSON data to the machine.
Let's take a look at examples to see the key syntax differences!
-```hjson
+```
{
# Comments are totally supported!
diff --git a/images/cairo/build.png b/images/cairo/build.png
new file mode 100644
index 00000000..7cadb9ad
--- /dev/null
+++ b/images/cairo/build.png
Binary files differ
diff --git a/images/cairo/connect.png b/images/cairo/connect.png
new file mode 100644
index 00000000..86146353
--- /dev/null
+++ b/images/cairo/connect.png
Binary files differ
diff --git a/images/cairo/connect2.png b/images/cairo/connect2.png
new file mode 100644
index 00000000..08b00a81
--- /dev/null
+++ b/images/cairo/connect2.png
Binary files differ
diff --git a/images/cairo/declare.png b/images/cairo/declare.png
new file mode 100644
index 00000000..5b5196ce
--- /dev/null
+++ b/images/cairo/declare.png
Binary files differ
diff --git a/images/cairo/deploy.png b/images/cairo/deploy.png
new file mode 100644
index 00000000..bdb7e53c
--- /dev/null
+++ b/images/cairo/deploy.png
Binary files differ
diff --git a/lbstanza.html.markdown b/lbstanza.html.markdown
index 06a38aef..90e7b7e5 100644
--- a/lbstanza.html.markdown
+++ b/lbstanza.html.markdown
@@ -8,7 +8,7 @@ contributors:
LB Stanza (or Stanza for short) is a new optionally-typed general purpose programming language from the University of California, Berkeley. Stanza was designed to help programmers tackle the complexity of architecting large programs and significantly increase the productivity of application programmers across the entire software development life cycle.
-```stanza
+```
; this is a comment
;<A>
This is a block comment
@@ -268,7 +268,7 @@ is-there = any?({_ == 2.0}, numbers)
doc: \<doc>
# Document Strings
- ```stanza
+ ```
val you-can = "include code snippets, too"
```
@@ -279,4 +279,4 @@ doc: \<doc>
```
\<doc>
defn docfn () : false
-``` \ No newline at end of file
+```
diff --git a/mips.html.markdown b/mips.html.markdown
index 31f735b0..3add0c5b 100644
--- a/mips.html.markdown
+++ b/mips.html.markdown
@@ -162,7 +162,7 @@ gateways and routers.
blt $t0, $t1, t0_gt_t1 # Branches when $t0 < $t1
ble $t0, $t1, t0_gte_t1 # Branches when $t0 <= $t1
bltz $t0, t0_lt0 # Branches when $t0 < 0
- slt $s0, $t0, $t1 # Instruction that sends a signal
+ slt $s0, $t0, $t1 # "Set on Less Than"
# when $t0 < $t1 with result in $s0
# (1 for true)
@@ -186,6 +186,7 @@ gateways and routers.
# else
# max = c;
# else
+ # if (b > c)
# max = b;
# else
# max = c;
@@ -212,8 +213,9 @@ gateways and routers.
# instruction to continue its execution
li $t0, 0
while:
- bgt $t0, 10, end_while # While $t0 is less than 10,
+ bgt $t0, 9, end_while # While $t0 is less than 10,
# keep iterating
+ #actual loop content would go here
addi $t0, $t0, 1 # Increment the value
j while # Jump back to the beginning of
# the loop
diff --git a/openscad.html.markdown b/openscad.html.markdown
index e09b5109..63570cbe 100644
--- a/openscad.html.markdown
+++ b/openscad.html.markdown
@@ -7,7 +7,7 @@ contributors:
Draw 3D models with code using [OpenSCAD](https://openscad.org/).
-```openscad
+```
// Comments look like this
// 3D Primitives
diff --git a/python.html.markdown b/python.html.markdown
index 175f17ec..d9eda60c 100644
--- a/python.html.markdown
+++ b/python.html.markdown
@@ -10,6 +10,7 @@ contributors:
- ["Roberto Fernandez Diaz", "https://github.com/robertofd1995"]
- ["caminsha", "https://github.com/caminsha"]
- ["Stanislav Modrak", "https://stanislav.gq"]
+ - ["John Paul Wohlscheid", "https://gitpi.us"]
filename: learnpython.py
---
@@ -84,7 +85,7 @@ False - 5 # => -5
# Comparison operators look at the numerical value of True and False
0 == False # => True
-1 == True # => True
+2 > True # => True
2 == True # => False
-5 != False # => True
@@ -1045,7 +1046,6 @@ print(say(say_please=True)) # Can you buy me a beer? Please! I am poor :(
### Free Online
* [Automate the Boring Stuff with Python](https://automatetheboringstuff.com)
-* [Ideas for Python Projects](http://pythonpracticeprojects.com)
* [The Official Docs](https://docs.python.org/3/)
* [Hitchhiker's Guide to Python](https://docs.python-guide.org/en/latest/)
* [Python Course](https://www.python-course.eu)
diff --git a/r.html.markdown b/r.html.markdown
index 2746d1eb..a063cc2f 100644
--- a/r.html.markdown
+++ b/r.html.markdown
@@ -12,7 +12,7 @@ R is a statistical computing language. It has lots of libraries for uploading an
```r
-# Comments start with number symbols.
+# Comments start with hash signs, also known as number symbols (#).
# You can't make multi-line comments,
# but you can stack multiple comments like so.
diff --git a/raku.html.markdown b/raku.html.markdown
index 53404f58..39bc0e51 100644
--- a/raku.html.markdown
+++ b/raku.html.markdown
@@ -122,7 +122,7 @@ say @array; # OUTPUT: «a 6 b␤»
# context, and any duplicated keys are deduplicated.
my %hash = 'a' => 1, 'b' => 2;
-# Keys get auto-quoted when the fat comman (`=>`) is used. Trailing commas are
+# Keys get auto-quoted when the fat comma (`=>`) is used. Trailing commas are
# okay.
%hash = a => 1, b => 2, ;
diff --git a/rust.html.markdown b/rust.html.markdown
index 9e07e005..c677ed96 100644
--- a/rust.html.markdown
+++ b/rust.html.markdown
@@ -223,7 +223,7 @@ fn main() {
type FunctionPointer = fn(u32) -> u32;
let fib : FunctionPointer = fibonacci;
- println!("Fib: {}", fib(4));
+ println!("Fib: {}", fib(4)); // 5
/////////////////////////
// 3. Pattern matching //
diff --git a/set-theory.html.markdown b/set-theory.html.markdown
index d55ab7d5..f89345c0 100644
--- a/set-theory.html.markdown
+++ b/set-theory.html.markdown
@@ -17,7 +17,7 @@ Set theory is a branch of mathematics that studies sets, their operations, and t
* the cross operator, `×`, means "the Cartesian product of".
### Qualifiers
-* the colon qualifier, `:`, means "such that";
+* the colon, `:`, or the vertical bar `|` qualifiers are interchangeable and mean "such that";
* the membership qualifier, `∈`, means "belongs to";
* the subset qualifier, `⊆`, means "is a subset of";
* the proper subset qualifier, `⊂`, means "is a subset of but is not equal to".
diff --git a/zh-cn/clojure-macro-cn.html.markdown b/zh-cn/clojure-macro-cn.html.markdown
index 23b2f203..85b966e9 100644
--- a/zh-cn/clojure-macro-cn.html.markdown
+++ b/zh-cn/clojure-macro-cn.html.markdown
@@ -131,7 +131,7 @@ lang: zh-cn
; 然而，如果我们希望它在编译期执行，就需要创建宏
(defmacro inline-2 [form]
- (inline-2-helper form)))
+ (inline-2-helper form))
(macroexpand '(inline-2 (1 + (3 / 2) - (1 / 2) + 1)))
; -> (+ (- (+ 1 (/ 3 2)) (/ 1 2)) 1)
diff --git a/zig.html.markdown b/zig.html.markdown
index 82c6b994..f8c866e5 100644
--- a/zig.html.markdown
+++ b/zig.html.markdown
@@ -39,7 +39,7 @@ Prior knowledge of C is recommended.
## Zig language
-```zig
+```
//! Top-level documentation.
/// Documentation comment.
@@ -49,7 +49,7 @@ Prior knowledge of C is recommended.
### Hello world.
-```zig
+```
// Import standard library, reachable through the "std" constant.
const std = @import("std");
@@ -67,7 +67,7 @@ pub fn main() void {
```
### Booleans, integers and float.
-```zig
+```
// Booleans.
// Keywords are preferred to operators for boolean operations.
print("{}\n{}\n{}\n", .{
@@ -109,7 +109,7 @@ i <<| 8 == 255 // u8: won't go higher than 255
```
### Arrays.
-```zig
+```
// An array is a well-defined structure with a length attribute (len).
// 5-byte array with undefined content (stack garbage).
@@ -156,7 +156,7 @@ try some_integers[i]; // Runtime error 'index out of bounds'.
```
### Multidimensional arrays.
-```zig
+```
const mat4x4 = [4][4]f32{
[_]f32{ 1.0, 0.0, 0.0, 0.0 },
@@ -177,7 +177,7 @@ for (mat4x4) |row, row_index| {
```
### Strings.
-```zig
+```
// Simple string constant.
const greetings = "hello";
@@ -195,7 +195,7 @@ print("string: {s}\n", .{greetings});
```
### Slices.
-```zig
+```
// A slice is a pointer and a size, an array without compile-time known size.
// Slices have runtime out-of-band verifications.
@@ -206,7 +206,7 @@ const slice = array[0..array.len]; // "slice" represents the whole array.
```
### Pointers.
-```zig
+```
// Pointer on a value can be created with "&".
const x: i32 = 1;
@@ -223,7 +223,7 @@ const foo = pointer.?; // Get the pointed value, otherwise crash.
```
### Optional values (?<type>).
-```zig
+```
// An optional is a value than can be of any type or null.
// Example: "optional_value" can either be "null" or an unsigned 32-bit integer.
@@ -239,7 +239,7 @@ if (x) |value| {
```
### Errors.
-```zig
+```
// Zig provides an unified way to express errors.
// Errors are defined in error enumerations, example:
@@ -299,7 +299,7 @@ var value = try some_function();
### Control flow.
-```zig
+```
// Conditional branching.
if (condition) {
@@ -384,7 +384,7 @@ const result = for (items) |value| {
```
### Labels.
-```zig
+```
// Labels are a way to name an instruction, a location in the code.
// Labels can be used to "continue" or "break" in a nested loop.
@@ -434,7 +434,7 @@ const result = for (items) |value| { // First: loop.
```
### Switch.
-```zig
+```
// As a switch in C, but slightly more advanced.
// Syntax:
@@ -461,7 +461,7 @@ const bar = switch (foo) {
```
### Structures.
-```zig
+```
// Structure containing a single value.
const Full = struct {
@@ -564,7 +564,7 @@ print("p.y: {}\n", .{p.y}); // 30
```
### Tuples.
-```zig
+```
// A tuple is a list of elements, possibly of different types.
const foo = .{ "hello", true, 42 };
@@ -572,7 +572,7 @@ const foo = .{ "hello", true, 42 };
```
### Enumerations.
-```zig
+```
const Type = enum { ok, not_ok };
@@ -606,7 +606,7 @@ const x = switch (direction) {
```
### Unions.
-```zig
+```
const Bar = union {
boolean: bool,
@@ -622,7 +622,7 @@ const foo: Bar = .{ .int = 42 };
```
### Tagged unions.
-```zig
+```
// Unions can be declared with an enum tag type, allowing them to be used in
// switch expressions.
@@ -653,7 +653,7 @@ switch (nay) {
```
### Defer and errdefer.
-```zig
+```
// Make sure that an action (single instruction or block of code) is executed
// before the end of the scope (function, block of code).
@@ -712,7 +712,7 @@ However, here are some examples, to get an idea of what you can expect:
Very simple way of avoiding leaks.
A first example.
-```zig
+```
// "!void" means the function doesn't return any value except for errors.
// In this case we try to allocate memory, and this may fail.
fn foo() !void {
@@ -735,7 +735,7 @@ fn foo() !void {
```
### Memory allocation combined with error management and defer.
-```zig
+```
fn some_memory_allocation_example() !void {
// Memory allocation may fail, so we "try" to allocate the memory and
@@ -759,7 +759,7 @@ fn some_memory_allocation_example() !void {
```
### Memory allocators: a taste of the standard library.
-```zig
+```
// Allocators: 4 main functions to know
// single_value = create (type)
@@ -846,7 +846,7 @@ fn gpa_arena_allocator_fn() !void {
```
### Comptime.
-```zig
+```
// Comptime is a way to avoid the pre-processor.
// The idea is simple: run code at compilation.
@@ -883,7 +883,7 @@ list.items[0] = 10;
```
### Conditional compilation.
-```zig
+```
const available_os = enum { OpenBSD, Linux };
const myos = available_os.OpenBSD;
@@ -905,7 +905,7 @@ const myprint = switch(myos) {
```
### Testing our functions.
-```zig
+```
const std = @import("std");
const expect = std.testing.expect;
@@ -936,7 +936,7 @@ There are more than a hundred built-ins, allowing very low-level stuff:
- etc.
Example: enums aren't integers, they have to be converted with a built-in.
-```zig
+```
const Value = enum { zero, stuff, blah };
if (@enumToInt(Value.zero) == 0) { ... }
if (@enumToInt(Value.stuff) == 1) { ... }