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<!DOCTYPE HTML>
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<ol class="chapter"><li class="chapter-item expanded affix "><a href="index.html">Introduction</a></li><li class="chapter-item expanded "><a href="quickstart/index.html"><strong aria-hidden="true">1.</strong> Quickstart</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="quickstart/installation.html"><strong aria-hidden="true">1.1.</strong> Installation</a></li><li class="chapter-item expanded "><a href="quickstart/first_contract.html"><strong aria-hidden="true">1.2.</strong> Write your first contract</a></li><li class="chapter-item expanded "><a href="quickstart/deploy_contract.html"><strong aria-hidden="true">1.3.</strong> Deploying a contract to a testnet</a></li></ol></li><li class="chapter-item expanded "><a href="development/index.html"><strong aria-hidden="true">2.</strong> Development</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="development/build.html"><strong aria-hidden="true">2.1.</strong> Build & Test</a></li><li class="chapter-item expanded "><a href="development/release.html"><strong aria-hidden="true">2.2.</strong> Release</a></li></ol></li><li class="chapter-item expanded "><a href="spec/index.html"><strong aria-hidden="true">3.</strong> Specification (WIP)</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/notation.html"><strong aria-hidden="true">3.1.</strong> Notation</a></li><li class="chapter-item expanded "><a href="spec/lexical_structure/index.html"><strong aria-hidden="true">3.2.</strong> Lexical Structure</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/lexical_structure/keywords.html"><strong aria-hidden="true">3.2.1.</strong> Keywords</a></li><li class="chapter-item expanded "><a href="spec/lexical_structure/identifiers.html"><strong aria-hidden="true">3.2.2.</strong> Identifiers</a></li><li class="chapter-item expanded "><a href="spec/lexical_structure/tokens.html"><strong aria-hidden="true">3.2.3.</strong> Tokens</a></li></ol></li><li class="chapter-item expanded "><a href="spec/comments.html"><strong aria-hidden="true">3.3.</strong> Comments</a></li><li class="chapter-item expanded "><a href="spec/items/index.html"><strong aria-hidden="true">3.4.</strong> Items</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/items/visibility_and_privacy.html"><strong aria-hidden="true">3.4.1.</strong> Visibility and Privacy</a></li><li class="chapter-item expanded "><a href="spec/items/functions.html"><strong aria-hidden="true">3.4.2.</strong> Functions</a></li><li class="chapter-item expanded "><a href="spec/items/structs.html"><strong aria-hidden="true">3.4.3.</strong> Structs</a></li><li class="chapter-item expanded "><a href="spec/items/events.html"><strong aria-hidden="true">3.4.4.</strong> Events</a></li><li class="chapter-item expanded "><a href="spec/items/enum.html"><strong aria-hidden="true">3.4.5.</strong> Enumeration</a></li><li class="chapter-item expanded "><a href="spec/items/type_aliases.html"><strong aria-hidden="true">3.4.6.</strong> Type Aliases</a></li><li class="chapter-item expanded "><a href="spec/items/contracts.html"><strong aria-hidden="true">3.4.7.</strong> Contracts</a></li></ol></li><li class="chapter-item expanded "><a href="spec/statements/index.html"><strong aria-hidden="true">3.5.</strong> Statements</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/statements/pragma.html"><strong aria-hidden="true">3.5.1.</strong> pragma Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/const.html"><strong aria-hidden="true">3.5.2.</strong> const Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/let.html"><strong aria-hidden="true">3.5.3.</strong> let Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/assign.html"><strong aria-hidden="true">3.5.4.</strong> Assignment Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/augassign.html"><strong aria-hidden="true">3.5.5.</strong> Augmenting Assignment Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/revert.html"><strong aria-hidden="true">3.5.6.</strong> revert Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/return.html"><strong aria-hidden="true">3.5.7.</strong> return Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/emit.html"><strong aria-hidden="true">3.5.8.</strong> emit Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/if.html"><strong aria-hidden="true">3.5.9.</strong> if Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/for.html"><strong aria-hidden="true">3.5.10.</strong> for Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/while.html"><strong aria-hidden="true">3.5.11.</strong> while Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/break.html"><strong aria-hidden="true">3.5.12.</strong> break Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/continue.html"><strong aria-hidden="true">3.5.13.</strong> continue Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/assert.html"><strong aria-hidden="true">3.5.14.</strong> assert Statement</a></li><li class="chapter-item expanded "><a href="spec/statements/pass.html"><strong aria-hidden="true">3.5.15.</strong> pass Statement</a></li></ol></li><li class="chapter-item expanded "><a href="spec/expressions/index.html"><strong aria-hidden="true">3.6.</strong> Expressions</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/expressions/call.html"><strong aria-hidden="true">3.6.1.</strong> Call expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/tuple.html"><strong aria-hidden="true">3.6.2.</strong> Tuple expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/list.html"><strong aria-hidden="true">3.6.3.</strong> List expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/struct.html"><strong aria-hidden="true">3.6.4.</strong> Struct expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/indexing.html"><strong aria-hidden="true">3.6.5.</strong> Index expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/attribute.html"><strong aria-hidden="true">3.6.6.</strong> Attribute expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/name.html"><strong aria-hidden="true">3.6.7.</strong> Name expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/literal.html"><strong aria-hidden="true">3.6.8.</strong> Literal expressions</a></li><li class="chapter-item expanded "><a href="spec/expressions/arithmetic_operators.html"><strong aria-hidden="true">3.6.9.</strong> Arithmetic Operators</a></li><li class="chapter-item expanded "><a href="spec/expressions/comparison_operators.html"><strong aria-hidden="true">3.6.10.</strong> Comparision Operators</a></li><li class="chapter-item expanded "><a href="spec/expressions/boolean_operators.html"><strong aria-hidden="true">3.6.11.</strong> Boolean Operators</a></li><li class="chapter-item expanded "><a href="spec/expressions/unary_operators.html"><strong aria-hidden="true">3.6.12.</strong> Unary Operators</a></li></ol></li><li class="chapter-item expanded "><a href="spec/type_system/index.html"><strong aria-hidden="true">3.7.</strong> Type System</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/type_system/types/index.html"><strong aria-hidden="true">3.7.1.</strong> Types</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/type_system/types/boolean.html"><strong aria-hidden="true">3.7.1.1.</strong> Boolean Type</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/contract.html"><strong aria-hidden="true">3.7.1.2.</strong> Contract Type</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/numeric.html"><strong aria-hidden="true">3.7.1.3.</strong> Numeric Types</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/tuple.html"><strong aria-hidden="true">3.7.1.4.</strong> Tuple Types</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/array.html"><strong aria-hidden="true">3.7.1.5.</strong> Array Types</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/struct.html"><strong aria-hidden="true">3.7.1.6.</strong> Struct Types</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/enum.html"><strong aria-hidden="true">3.7.1.7.</strong> Enumerated Types</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/address.html"><strong aria-hidden="true">3.7.1.8.</strong> Address Type</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/map.html"><strong aria-hidden="true">3.7.1.9.</strong> Map Type</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/string.html"><strong aria-hidden="true">3.7.1.10.</strong> String Type</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/unit.html"><strong aria-hidden="true">3.7.1.11.</strong> Unit Type</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/event.html"><strong aria-hidden="true">3.7.1.12.</strong> Event Types</a></li><li class="chapter-item expanded "><a href="spec/type_system/types/function.html"><strong aria-hidden="true">3.7.1.13.</strong> Function Type</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="spec/data_layout/index.html"><strong aria-hidden="true">3.8.</strong> Data Layout</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/data_layout/stack.html"><strong aria-hidden="true">3.8.1.</strong> Stack</a></li><li class="chapter-item expanded "><a href="spec/data_layout/storage/index.html"><strong aria-hidden="true">3.8.2.</strong> Storage</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/data_layout/storage/constant_size_values_in_storage.html"><strong aria-hidden="true">3.8.2.1.</strong> Constant size values in storage</a></li><li class="chapter-item expanded "><a href="spec/data_layout/storage/maps_in_storage.html"><strong aria-hidden="true">3.8.2.2.</strong> Maps in storage</a></li><li class="chapter-item expanded "><a href="spec/data_layout/storage/to_mem_function.html"><strong aria-hidden="true">3.8.2.3.</strong> to_mem() function</a></li></ol></li><li class="chapter-item expanded "><a href="spec/data_layout/memory/index.html"><strong aria-hidden="true">3.8.3.</strong> Memory</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="spec/data_layout/memory/sequence_types_in_memory.html"><strong aria-hidden="true">3.8.3.1.</strong> Sequence types in memory</a></li><li class="chapter-item expanded "><a href="spec/data_layout/memory/clone_function.html"><strong aria-hidden="true">3.8.3.2.</strong> clone() function</a></li></ol></li></ol></li><li class="chapter-item expanded "><a href="spec/function_calls.html"><strong aria-hidden="true">3.9.</strong> Function calls</a></li></ol></li><li class="chapter-item expanded "><a href="release_notes.html" class="active"><strong aria-hidden="true">4.</strong> Release Notes</a></li><li class="chapter-item expanded "><a href="code_of_conduct.html"><strong aria-hidden="true">5.</strong> Code of Conduct</a></li></ol>
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<h1 id="release-notes"><a class="header" href="#release-notes">Release Notes</a></h1>
<p><a href="https://github.com/ethereum/fe/releases">🖥️ Download Binaries</a>
<a href="https://github.com/ethereum/fe/tree/master/spec">📄 Draft Spec</a>
<a href="https://github.com/ethereum/fe#getting-started">ℹ️ Getting Started</a></p>
<p>Fe is moving fast. Read up on all the latest improvements.</p>
<p><strong>WARNING: All Fe releases are alpha releases and only meant to share the development progress with developers and enthusiasts. It is NOT yet ready for production usage.</strong></p>
<h2 id="0160-alpha-2022-05-05"><a class="header" href="#0160-alpha-2022-05-05">0.16.0-alpha (2022-05-05)</a></h2>
<h3 id="features"><a class="header" href="#features">Features</a></h3>
<ul>
<li>Change static function call syntax from <code>Bar.foo()</code> to <code>Bar::foo()</code> (<a href="https://github.com/ethereum/fe/issues/241">#241</a>)</li>
<li>Added support for retrieving the base fee via <code>ctx.base_fee()</code> (<a href="https://github.com/ethereum/fe/issues/503">#503</a>)</li>
</ul>
<h3 id="bugfixes"><a class="header" href="#bugfixes">Bugfixes</a></h3>
<ul>
<li>Resolve functions on structs via path (e.g. <code>bi::ba::bums()</code>) (<a href="https://github.com/ethereum/fe/issues/241">#241</a>)</li>
</ul>
<h2 id="0150-alpha-2022-04-04"><a class="header" href="#0150-alpha-2022-04-04">0.15.0-alpha (2022-04-04)</a></h2>
<h3 id="features-1"><a class="header" href="#features-1">Features</a></h3>
<ul>
<li>
<p>Labels are now required on function arguments. Labels can be omitted if the
argument is a variable with a name that matches the label, or if the function
definition specifies that an argument should have no label. Functions often take
several arguments of the same type; compiler-checked labels can help prevent
accidentally providing arguments in the wrong order.</p>
<p>Example:</p>
<pre><code>contract CoolCoin:
balance: Map<address, i256>
loans: Map<(address, address), i256>
pub fn demo(self, ann: address, bob: address):
let is_loan: bool = false
self.give(from: ann, to: bob, 100, is_loan)
fn transfer(self, from sender: address, to recipient: address, _ val: u256, is_loan: bool):
self.cred[sender] -= val
self.cred[recipient] += val
if is_loan:
self.loans[(sender, recipient)] += val
</code></pre>
<p>Note that arguments must be provided in the order specified in the function
definition.</p>
<p>A parameter's label defaults to the parameter name, but can be changed by
specifying a different label to the left of the parameter name. Labels should be
clear and convenient for the caller, while parameter names are only used in the
function body, and can thus be longer and more descriptive.
In the example above, we choose to use <code>sender</code> and <code>recipient</code> as identifiers
in the body of <code>fn transfer</code>, but use labels <code>from:</code> and <code>to:</code>.</p>
<p>In cases where it's ideal to not have labels, e.g. if a function takes a single
argument, or if types are sufficient to differentiate between arguments, use <code>_</code>
to specify that a given parameter has no label. It's also fine to require labels
for some arguments, but not others.</p>
<p>Example:</p>
<pre><code>fn add(_ x: u256, _ y: u256) -> u256:
return x + y
contract Foo:
fn transfer(self, _ to: address, wei: u256):
pass
pub fn demo(self):
transfer(address(0), wei: add(1000, 42))
``` ([#397](https://github.com/ethereum/fe/issues/397))
</code></pre>
</li>
</ul>
<h3 id="bugfixes-1"><a class="header" href="#bugfixes-1">Bugfixes</a></h3>
<ul>
<li>The region of memory used to compute the slot of a storage map value was not being allocated. (<a href="https://github.com/ethereum/fe/issues/684">#684</a>)</li>
</ul>
<h2 id="0140-alpha-2022-03-02"><a class="header" href="#0140-alpha-2022-03-02">0.14.0-alpha (2022-03-02)</a></h2>
<h3 id="features-2"><a class="header" href="#features-2">Features</a></h3>
<ul>
<li>
<p>Events can now be defined outside of contracts.</p>
<p>Example:</p>
<pre><code>event Transfer:
idx sender: address
idx receiver: address
value: u256
contract Foo:
fn transferFoo(to: address, value: u256):
emit Transfer(sender: msg.sender, receiver: to, value)
contract Bar:
fn transferBar(to: address, value: u256):
emit Transfer(sender: msg.sender, receiver: to, value)
``` ([#80](https://github.com/ethereum/fe/issues/80))
</code></pre>
</li>
<li>
<p>The Fe standard library now includes a <code>std::evm</code> module, which provides functions that perform low-level evm operations.
Many of these are marked <code>unsafe</code>, and thus can only be used inside of an <code>unsafe</code> function or an <code>unsafe</code> block.</p>
<p>Example:</p>
<pre><code>use std::evm::{mstore, mload}
fn memory_shenanigans():
unsafe:
mstore(0x20, 42)
let x: u256 = mload(0x20)
assert x == 42
</code></pre>
<p>The global functions <code>balance</code> and <code>balance_of</code> have been removed; these can now be called as <code>std::evm::balance()</code>, etc.
The global function <code>send_value</code> has been ported to Fe, and is now available as <code>std::send_value</code>. (<a href="https://github.com/ethereum/fe/issues/629">#629</a>)</p>
</li>
<li>
<p>Support structs that have non-base type fields in storage.</p>
<p>Example:</p>
<pre><code>struct Point:
pub x: u256
pub y: u256
struct Bar:
pub name: String<3>
pub numbers: Array<u256, 2>
pub point: Point
pub something: (u256, bool)
contract Foo:
my_bar: Bar
pub fn complex_struct_in_storage(self) -> String<3>:
self.my_bar = Bar(
name: "foo",
numbers: [1, 2],
point: Point(x: 100, y: 200),
something: (1, true),
)
# Asserting the values as they were set initially
assert self.my_bar.numbers[0] == 1
assert self.my_bar.numbers[1] == 2
assert self.my_bar.point.x == 100
assert self.my_bar.point.y == 200
assert self.my_bar.something.item0 == 1
assert self.my_bar.something.item1
# We can change the values of the array
self.my_bar.numbers[0] = 10
self.my_bar.numbers[1] = 20
assert self.my_bar.numbers[0] == 10
assert self.my_bar.numbers[1] == 20
# We can set the array itself
self.my_bar.numbers = [1, 2]
assert self.my_bar.numbers[0] == 1
assert self.my_bar.numbers[1] == 2
# We can change the values of the Point
self.my_bar.point.x = 1000
self.my_bar.point.y = 2000
assert self.my_bar.point.x == 1000
assert self.my_bar.point.y == 2000
# We can set the point itself
self.my_bar.point = Point(x=100, y=200)
assert self.my_bar.point.x == 100
assert self.my_bar.point.y == 200
# We can change the value of the tuple
self.my_bar.something.item0 = 10
self.my_bar.something.item1 = false
assert self.my_bar.something.item0 == 10
assert not self.my_bar.something.item1
# We can set the tuple itself
self.my_bar.something = (1, true)
assert self.my_bar.something.item0 == 1
assert self.my_bar.something.item1
return self.my_bar.name.to_mem()
``` ([#636](https://github.com/ethereum/fe/issues/636))
</code></pre>
</li>
<li>
<p>Features that read and modify state outside of contracts are now implemented on a struct
named "Context". <code>Context</code> is included in the standard library and can be imported with
<code>use std::context::Context</code>. Instances of <code>Context</code> are created by calls to public functions
that declare it in the signature or by unsafe code.</p>
<p>Basic example:</p>
<pre><code>use std::context::Context
contract Foo:
my_num: u256
pub fn baz(ctx: Context) -> u256:
return ctx.block_number()
pub fn bing(self, new_num: u256) -> u256:
self.my_num = new_num
return self.my_num
contract Bar:
pub fn call_baz(ctx: Context, foo_addr: address) -> u256:
# future syntax: `let foo = ctx.load<Foo>(foo_addr)`
let foo: Foo = Foo(ctx, foo_addr)
return foo.baz()
pub fn call_bing(ctx: Context) -> u256:
# future syntax: `let foo = ctx.create<Foo>(0)`
let foo: Foo = Foo.create(ctx, 0)
return foo.bing(42)
</code></pre>
<p>Example with <code>__call__</code> and unsafe block:</p>
<pre><code>use std::context::Context
use std::evm
contract Foo:
pub fn __call__():
unsafe:
# creating an instance of `Context` is unsafe
let ctx: Context = Context()
let value: u256 = u256(bar(ctx))
# return `value`
evm::mstore(0, value)
evm::return_mem(0, 32)
fn bar(ctx: Context) -> address:
return ctx.self_address()
``` ([#638](https://github.com/ethereum/fe/issues/638))
</code></pre>
</li>
<li>
<h1 id="features-3"><a class="header" href="#features-3">Features</a></h1>
<h2 id="support-local-constant"><a class="header" href="#support-local-constant">Support local constant</a></h2>
<p>Example:</p>
<pre><code class="language-python">contract Foo:
pub fn bar():
const LOCAL_CONST: i32 = 1
</code></pre>
<h2 id="support-constant-expression"><a class="header" href="#support-constant-expression">Support constant expression</a></h2>
<p>Example:</p>
<pre><code class="language-python">const GLOBAL: i32 = 8
contract Foo:
pub fn bar():
const LOCAL: i32 = GLOBAL * 8
</code></pre>
<h2 id="support-constant-generics-expression"><a class="header" href="#support-constant-generics-expression">Support constant generics expression</a></h2>
<p>Example:</p>
<pre><code class="language-python">const GLOBAL: u256= 8
const USE_GLOBAL: bool = false
type MY_ARRAY = Array<i32, { GLOBAL / 4 }>
contract Foo:
pub fn bar():
let my_array: Array<i32, { GLOBAL if USE_GLOBAL else 4 }>
</code></pre>
<h1 id="bug-fixes"><a class="header" href="#bug-fixes">Bug fixes</a></h1>
<h2 id="fix-ice-when-constant-type-is-mismatch"><a class="header" href="#fix-ice-when-constant-type-is-mismatch">Fix ICE when constant type is mismatch</a></h2>
<p>Example:</p>
<pre><code class="language-python">const GLOBAL: i32 = "FOO"
contract Foo:
pub fn bar():
let FOO: i32 = GLOBAL
</code></pre>
<h2 id="fix-ice-when-assigning-value-to-constant-twice"><a class="header" href="#fix-ice-when-assigning-value-to-constant-twice">Fix ICE when assigning value to constant twice</a></h2>
<p>Example:</p>
<pre><code class="language-python">const BAR: i32 = 1
contract FOO:
pub fn bar():
BAR = 10
``` ([#649](https://github.com/ethereum/fe/issues/649))
</code></pre>
</li>
<li>
<p>Argument label syntax now uses <code>:</code> instead of <code>=</code>. Example:</p>
<pre><code>struct Foo:
x: u256
y: u256
let x: MyStruct = MyStruct(x: 10, y: 11)
# previously: MyStruct(x = 10, y = 11)
``` ([#665](https://github.com/ethereum/fe/issues/665))
</code></pre>
</li>
<li>
<p>Support module-level <code>pub</code> modifier, now default visibility of items in a module is private.</p>
<p>Example:</p>
<pre><code class="language-python"># This constant can be used outside of the module.
pub const PUBLIC:i32 = 1
# This constant can NOT be used outside of the module.
const PRIVATE: i32 = 1
``` ([#677](https://github.com/ethereum/fe/issues/677))
</code></pre>
</li>
</ul>
<h3 id="internal-changes---for-fe-contributors"><a class="header" href="#internal-changes---for-fe-contributors">Internal Changes - for Fe Contributors</a></h3>
<ul>
<li>
<ul>
<li>Source files are now managed by a (salsa) <code>SourceDb</code>. A <code>SourceFileId</code> now corresponds to a salsa-interned <code>File</code> with a path. File content is a salsa input function. This is mostly so that the future (LSP) language server can update file content when the user types or saves, which will trigger a re-analysis of anything that changed.</li>
<li>An ingot's set of modules and dependencies are also salsa inputs, so that when the user adds/removes a file or dependency, analysis is rerun.</li>
<li>Standalone modules (eg a module compiled with <code>fe fee.fe</code>) now have a fake ingot parent. Each Ingot has an IngotMode (Lib, Main, StandaloneModule), which is used to disallow <code>ingot::whatever</code> paths in standalone modules, and to determine the correct root module file.</li>
<li><code>parse_module</code> now always returns an <code>ast::Module</code>, and thus a <code>ModuleId</code> will always exist for a source file, even if it contains fatal parse errors. If the parsing fails, the body will end with a <code>ModuleStmt::ParseError</code> node. The parsing will stop at all but the simplest of syntax errors, but this at least allows partial analysis of source file with bad syntax.</li>
<li><code>ModuleId::ast(db)</code> is now a query that parses the module's file on demand, rather than the AST being interned into salsa. This makes handling parse diagnostics cleaner, and removes the up-front parsing of every module at ingot creation time. (<a href="https://github.com/ethereum/fe/issues/628">#628</a>)</li>
</ul>
</li>
</ul>
<h2 id="0130-alpha-2022-01-31-0130-alpha-2022-01-31"><a class="header" href="#0130-alpha-2022-01-31-0130-alpha-2022-01-31">0.13.0-alpha (2022-01-31)## 0.13.0-alpha (2022-01-31)</a></h2>
<h3 id="features-4"><a class="header" href="#features-4">Features</a></h3>
<ul>
<li>
<p>Support private fields on structs</p>
<p>Public fields now need to be declared with the <code>pub</code> modifier, otherwise they default to private fields.
If a struct contains private fields it can not be constructed directly except from within the
struct itself. The recommended way is to implement a method <code>new(...)</code> as demonstrated in the
following example.</p>
<pre><code>struct House:
pub price: u256
pub size: u256
vacant: bool
pub fn new(price: u256, size: u256) -> House
return House(price=price, size=size, vacant=true)
contract Manager:
house: House
pub fn create_house(price: u256, size: u256):
self.house = House::new(price, size)
let can_access_price: u256 = self.house.price
# can not access `self.house.vacant` because the field is private
``` ([#214](https://github.com/ethereum/fe/issues/214))
</code></pre>
</li>
<li>
<p>Support non-base type fields in structs</p>
<p>Support is currently limited in two ways:</p>
<ul>
<li>Structs with complex fields can not be returned from public functions</li>
<li>Structs with complex fields can not be stored in storage (<a href="https://github.com/ethereum/fe/issues/343">#343</a>)</li>
</ul>
</li>
<li>
<p>Addresses can now be explicitly cast to u256. For example:</p>
<pre><code>fn f(addr: address) -> u256:
return u256(addr)
``` ([#621](https://github.com/ethereum/fe/issues/621))
</code></pre>
</li>
<li>
<p>A special function named <code>__call__</code> can now be defined in contracts. </p>
<p>The body of this function will execute in place of the standard dispatcher when the contract is called.</p>
<p>example (with intrinsics):</p>
<pre><code>contract Foo:
pub fn __call__(self):
unsafe:
if __calldataload(0) == 1:
__revert(0, 0)
else:
__return(0, 0)
``` ([#622](https://github.com/ethereum/fe/issues/622))
</code></pre>
</li>
</ul>
<h3 id="bugfixes-2"><a class="header" href="#bugfixes-2">Bugfixes</a></h3>
<ul>
<li>
<p>Fixed a crash that happend when using a certain unprintable ASCII char (<a href="https://github.com/ethereum/fe/issues/551">#551</a>)</p>
</li>
<li>
<p>The argument to <code>revert</code> wasn't being lowered by the compiler,
meaning that some <code>revert</code> calls would cause a compiler panic
in later stages. For example:</p>
<pre><code>const BAD_MOJO: u256 = 0xdeaddead
struct Error:
code: u256
fn fail():
revert Error(code = BAD_MOJO)
``` ([#619](https://github.com/ethereum/fe/issues/619))
</code></pre>
</li>
<li>
<p>Fixed a regression where an empty list expression (<code>[]</code>) would lead to a compiler crash. (<a href="https://github.com/ethereum/fe/issues/623">#623</a>)</p>
</li>
<li>
<p>Fixed a bug where int array elements were not sign extended in their ABI encodings. (<a href="https://github.com/ethereum/fe/issues/633">#633</a>)</p>
</li>
</ul>
<h2 id="0120-alpha-2021-12-31-0120-alpha-2021-12-31"><a class="header" href="#0120-alpha-2021-12-31-0120-alpha-2021-12-31">0.12.0-alpha (2021-12-31)## 0.12.0-alpha (2021-12-31)</a></h2>
<h3 id="features-5"><a class="header" href="#features-5">Features</a></h3>
<ul>
<li>
<p>Added unsafe low-level "intrinsic" functions, that perform raw evm operations.
For example:</p>
<pre><code>fn foo():
unsafe:
__mtore(0, 5000)
assert __mload(0) == 5000
</code></pre>
<p>The functions available are exactly those defined in yul's "evm dialect":
https://docs.soliditylang.org/en/v0.8.11/yul.html#evm-dialect
but with a double-underscore prefix. Eg <code>selfdestruct</code> -> <code>__selfdestruct</code>.</p>
<p>These are intended to be used for implementing basic standard library functionality,
and shouldn't typically be needed in normal contract code.</p>
<p>Note: some intrinsic functions don't return a value (eg <code>__log0</code>); using these
functions in a context that assumes a return value of unit type (eg <code>let x: () = __log0(a, b)</code>)
will currently result in a compiler panic in the yul compilation phase. (<a href="https://github.com/ethereum/fe/issues/603">#603</a>)</p>
</li>
<li>
<p>Added an out of bounds check for accessing array items.
If an array index is retrieved at an index that is not within
the bounds of the array it now reverts with <code>Panic(0x32)</code>. (<a href="https://github.com/ethereum/fe/issues/606">#606</a>)</p>
</li>
</ul>
<h3 id="bugfixes-3"><a class="header" href="#bugfixes-3">Bugfixes</a></h3>
<ul>
<li>
<p>Ensure ternary expression short circuit.</p>
<p>Example:</p>
<pre><code>contract Foo:
pub fn bar(input: u256) -> u256:
return 1 if input > 5 else revert_me()
fn revert_me() -> u256:
revert
return 0
</code></pre>
<p>Previous to this change, the code above would <strong>always</strong> revert no matter
which branch of the ternary expressions it would resolve to. That is because
both sides were evaluated and then one side was discarded. With this change,
only the branch that doesn't get picked won't get evaluated at all.</p>
<p>The same is true for the boolean operations <code>and</code> and <code>or</code>. (<a href="https://github.com/ethereum/fe/issues/488">#488</a>)</p>
</li>
</ul>
<h3 id="internal-changes---for-fe-contributors-1"><a class="header" href="#internal-changes---for-fe-contributors-1">Internal Changes - for Fe Contributors</a></h3>
<ul>
<li>
<p>Added a globally available <em>dummy</em> std lib.</p>
<p>This library contains a single <code>get_42</code> function, which can be called using <code>std::get_42()</code>. Once
low-level intrinsics have been added to the language, we can delete <code>get_42</code> and start adding
useful code. (<a href="https://github.com/ethereum/fe/issues/601">#601</a>)</p>
</li>
</ul>
<h2 id="0110-alpha-karlite-2021-12-02"><a class="header" href="#0110-alpha-karlite-2021-12-02">0.11.0-alpha "Karlite" (2021-12-02)</a></h2>
<h3 id="features-6"><a class="header" href="#features-6">Features</a></h3>
<ul>
<li>
<p>Added support for multi-file inputs.</p>
<p><strong>Implementation details:</strong></p>
<p>Mostly copied Rust's crate system, but use the the term <em>ingot</em> instead of crate.</p>
<p>Below is an example of an ingot's file tree, as supported by the current implementation.</p>
<pre><code>`-- basic_ingot
`-- src
|-- bar
| `-- baz.fe
|-- bing.fe
|-- ding
| |-- dang.fe
| `-- dong.fe
`-- main.fe
</code></pre>
<p>There are still a few features that will be worked on over the coming months:</p>
<ul>
<li>source files accompanying each directory module (e.g. <code>my_mod.fe</code>)</li>
<li>configuration files and the ability to create library ingots</li>
<li>test directories</li>
<li>module-level <code>pub</code> modifier (all items in a module are public)</li>
<li><code>mod</code> statements (all fe files in the input tree are public modules)</li>
</ul>
<p>These things will be implemented in order of importance over the next few months. (<a href="https://github.com/ethereum/fe/issues/562">#562</a>)</p>
</li>
<li>
<p>The syntax for array types has changed to match other generic types.
For example, <code>u8[4]</code> is now written <code>Array<u8, 4></code>. (<a href="https://github.com/ethereum/fe/issues/571">#571</a>)</p>
</li>
<li>
<p>Functions can now be defined on struct types. Example:</p>
<pre><code>struct Point:
x: u64
y: u64
# Doesn't take `self`. Callable as `Point.origin()`.
# Note that the syntax for this will soon be changed to `Point::origin()`.
pub fn origin() -> Point:
return Point(x=0, y=0)
# Takes `self`. Callable on a value of type `Point`.
pub fn translate(self, x: u64, y: u64):
self.x += x
self.y += y
pub fn add(self, other: Point) -> Point:
let x: u64 = self.x + other.x
let y: u64 = self.y + other.y
return Point(x, y)
pub fn hash(self) -> u256:
return keccak256(self.abi_encode())
pub fn do_pointy_things():
let p1: Point = Point.origin()
p1.translate(5, 10)
let p2: Point = Point(x=1, y=2)
let p3: Point = p1.add(p2)
assert p3.x == 6 and p3.y == 12
``` ([#577](https://github.com/ethereum/fe/issues/577))
</code></pre>
</li>
</ul>
<h3 id="bugfixes-4"><a class="header" href="#bugfixes-4">Bugfixes</a></h3>
<ul>
<li>
<p>Fixed a rare compiler crash.</p>
<p>Example:</p>
<pre><code>let my_array: i256[1] = [-1 << 1]
</code></pre>
<p>Previous to this fix, the given example would lead to an ICE. (<a href="https://github.com/ethereum/fe/issues/550">#550</a>)</p>
</li>
<li>
<p>Contracts can now <code>create</code> an instance of a contract defined later in a file.
This issue was caused by a weakness in the way we generated yul. (<a href="https://github.com/ethereum/fe/issues/596">#596</a>)</p>
</li>
</ul>
<h3 id="internal-changes---for-fe-contributors-2"><a class="header" href="#internal-changes---for-fe-contributors-2">Internal Changes - for Fe Contributors</a></h3>
<ul>
<li>
<p>File IDs are now attached to <code>Span</code>s. (<a href="https://github.com/ethereum/fe/issues/587">#587</a>)</p>
</li>
<li>
<p>The fe analyzer now builds a dependency graph of source code "items" (functions, contracts, structs, etc).
This is used in the yulgen phase to determine which items are needed in the yul (intermediate representation)
output. Note that the yul output is still cluttered with utility functions that may or may not be needed by
a given contract. These utility functions are defined in the yulgen phase and aren't tracked in the dependency
graph, so it's not yet possible to filter out the unused functions. We plan to move the definition of many
of these utility functions into fe; when this happens they'll become part of the dependency graph and will only
be included in the yul output when needed.</p>
<p>The dependency graph will also enable future analyzer warnings about unused code. (<a href="https://github.com/ethereum/fe/issues/596">#596</a>)</p>
</li>
</ul>
<h2 id="0100-alpha-2021-10-31"><a class="header" href="#0100-alpha-2021-10-31">0.10.0-alpha (2021-10-31)</a></h2>
<h3 id="features-7"><a class="header" href="#features-7">Features</a></h3>
<ul>
<li>
<p>Support for module level constants for base types</p>
<p>Example:</p>
<pre><code>const TEN = 10
contract
pub fn do_moon_math(self) -> u256:
return 4711 * TEN
</code></pre>
<p>The values of base type constants are always inlined. (<a href="https://github.com/ethereum/fe/issues/192">#192</a>)</p>
</li>
<li>
<p>Encode revert errors for ABI decoding as <code>Error(0x103)</code> not <code>Panic(0x99)</code> (<a href="https://github.com/ethereum/fe/issues/492">#492</a>)</p>
</li>
<li>
<p>Replaced <code>import</code> statements with <code>use</code> statements.</p>
<p>Example:</p>
<pre><code>use foo::{bar::*, baz as baz26}
</code></pre>
<p>Note: this only adds support for parsing <code>use</code> statements. (<a href="https://github.com/ethereum/fe/issues/547">#547</a>)</p>
</li>
<li>
<p>Functions can no be defined outside of contracts. Example:</p>
<pre><code>fn add_bonus(x: u256) -> u256:
return x + 10
contract PointTracker:
points: Map<address, u256>
pub fn add_points(self, user: address, val: u256):
self.points[user] += add_bonus(val)
``` ([#566](https://github.com/ethereum/fe/issues/566))
</code></pre>
</li>
<li>
<p>Implemented a <code>send_value(to: address, value_in_wei: u256)</code> function.</p>
<p>The function is similar to the <a href="https://github.com/OpenZeppelin/openzeppelin-contracts/blob/5b28259dacf47fc208e03611eb3ba8eeaed63cc0/contracts/utils/Address.sol#L54-L59"><code>sendValue</code> function by OpenZeppelin</a> with the differences being that:</p>
<ol>
<li>
<p>It reverts with <code>Error(0x100)</code> instead of <code>Error("Address: insufficient balance")</code> to
safe more gas.</p>
</li>
<li>
<p>It uses <code>selfbalance()</code> instead of <code>balance(address())</code> to safe more gas</p>
</li>
<li>
<p>It reverts with <code>Error(0x101)</code> instead of <code>Error("Address: unable to send value, recipient may have reverted")</code> also to safe more gas. (<a href="https://github.com/ethereum/fe/issues/567">#567</a>)</p>
</li>
</ol>
</li>
<li>
<p>Added support for <code>unsafe</code> functions and <code>unsafe</code> blocks within functions.
Note that there's currently no functionality within Fe that requires the use
of <code>unsafe</code>, but we plan to add built-in <code>unsafe</code> functions that perform raw
evm operations which will only callable within an <code>unsafe</code> block or function. (<a href="https://github.com/ethereum/fe/issues/569">#569</a>)</p>
</li>
<li>
<p>Added <code>balance()</code> and <code>balance_of(account: address)</code> methods. (<a href="https://github.com/ethereum/fe/issues/572">#572</a>)</p>
</li>
<li>
<p>Added support for explicit casting between numeric types.</p>
<p>Example:</p>
<pre><code>let a: i8 = i8(-1)
let a1: i16 = i16(a)
let a2: u16 = u16(a1)
assert a2 == u16(65535)
let b: i8 = i8(-1)
let b1: u8 = u8(b)
let b2: u16 = u16(b1)
assert b2 == u16(255)
</code></pre>
<p>Notice that Fe allows casting between any two numeric types but does not allow
to change both the sign and the size of the type in one step as that would leave
room for ambiguity as the example above demonstrates. (<a href="https://github.com/ethereum/fe/issues/576">#576</a>)</p>
</li>
</ul>
<h3 id="bugfixes-5"><a class="header" href="#bugfixes-5">Bugfixes</a></h3>
<ul>
<li>
<p>Adjust numeric values loaded from memory or storage</p>
<p>Previous to this fix numeric values that were loaded from either memory or storage
were not properly loaded on the stack which could result in numeric values not
treated as intended.</p>
<p>Example:</p>
<pre><code>contract Foo:
pub fn bar() -> i8:
let in_memory: i8[1] = [-3]
return in_memory[0]
</code></pre>
<p>In the example above <code>bar()</code> would not return <code>-3</code> but <code>253</code> instead. (<a href="https://github.com/ethereum/fe/issues/524">#524</a>)</p>
</li>
<li>
<p>Propagate reverts from external contract calls.</p>
<p>Before this fix the following code to <code>should_revert()</code> or <code>should_revert2()</code>
would succeed even though it clearly should not.</p>
<pre><code>contract A:
contract_b: B
pub fn __init__(contract_b: address):
self.contract_b = B(contract_b)
pub fn should_revert():
self.contract_b.fail()
pub fn should_revert2():
self.contract_b.fail_with_custom_error()
struct SomeError:
pass
contract B:
pub fn fail():
revert
pub fn fail_with_custom_error():
revert SomeError()
</code></pre>
<p>With this fix the revert errors are properly passed upwards the call hierachy. (<a href="https://github.com/ethereum/fe/issues/574">#574</a>)</p>
</li>
<li>
<p>Fixed bug in left shift operation.</p>
<p>Example:</p>
<p>Let's consider the value <code>1</code> as an <code>u8</code> which is represented as
the following 256 bit item on the EVM stack <code>00..|00000001|</code>.
A left shift of <code>8</code> bits (<code>val << 8</code>) turns that into <code>00..01|00000000|</code>.</p>
<p>Previous to this fix this resulted in the compiler taking <code>256</code> as the
value for the <code>u8</code> when clearly <code>256</code> is not even in the range of <code>u8</code>
anymore. With this fix the left shift operations was fixed to properly
"clean up" the result of the shift so that <code>00..01|00000000|</code> turns into
<code>00..00|00000000|</code>. (<a href="https://github.com/ethereum/fe/issues/575">#575</a>)</p>
</li>
<li>
<p>Ensure negation is checked and reverts with over/underflow if needed.</p>
<p>Example:</p>
<p>The minimum value for an <code>i8</code> is <code>-128</code> but the maximum value of an <code>i8</code>
is <code>127</code> which means that negating <code>-128</code> should lead to an overflow since
<code>128</code> does not fit into an <code>i8</code>. Before this fix, negation operations where
not checked for over/underflow resulting in returning the oversized value. (<a href="https://github.com/ethereum/fe/issues/578">#578</a>)</p>
</li>
</ul>
<h3 id="internal-changes---for-fe-contributors-3"><a class="header" href="#internal-changes---for-fe-contributors-3">Internal Changes - for Fe Contributors</a></h3>
<ul>
<li>
<p>In the analysis stage, all name resolution (of variable names, function names,
type names, etc used in code) now happens via a single <code>resolve_name</code> pathway,
so we can catch more cases of name collisions and log more helpful error messages. (<a href="https://github.com/ethereum/fe/issues/555">#555</a>)</p>
</li>
<li>
<p>Added a new category of tests: differential contract testing.</p>
<p>Each of these tests is pased on a pair of contracts where one implementation
is written in Fe and the other one is written in Solidity. The implementations
should have the same public APIs and are assumed to always return identical
results given equal inputs. The inputs are randomly generated using <code>proptest</code>
and hence are expected to discover unknown bugs. (<a href="https://github.com/ethereum/fe/issues/578">#578</a>)</p>
</li>
</ul>
<h2 id="090-alpha-2021-09-29"><a class="header" href="#090-alpha-2021-09-29">0.9.0-alpha (2021-09-29)</a></h2>
<h3 id="features-8"><a class="header" href="#features-8">Features</a></h3>
<ul>
<li>
<p>The <code>self</code> variable is no longer implicitly defined in code blocks. It must now be declared
as the first parameter in a function signature.</p>
<p>Example:</p>
<pre><code>contract Foo:
my_stored_num: u256
pub fn bar(self, my_num: u256):
self.my_stored_num = my_num
pub fn baz(self):
self.bar(my_pure_func())
pub fn my_pure_func() -> u256:
return 42 + 26
``` ([#520](https://github.com/ethereum/fe/issues/520))
</code></pre>
</li>
<li>
<p>The analyzer now disallows defining a type, variable, or function whose
name conflicts with a built-in type, function, or object.</p>
<p>Example:</p>
<pre><code>error: type name conflicts with built-in type
┌─ compile_errors/shadow_builtin_type.fe:1:6
│
1 │ type u256 = u8
│ ^^^^ `u256` is a built-in type
``` ([#539](https://github.com/ethereum/fe/issues/539))
</code></pre>
</li>
</ul>
<h3 id="bugfixes-6"><a class="header" href="#bugfixes-6">Bugfixes</a></h3>
<ul>
<li>Fixed cases where the analyzer would correctly reject code, but would panic instead of logging an error message. (<a href="https://github.com/ethereum/fe/issues/534">#534</a>)</li>
<li>Non-fatal parser errors (eg missing parentheses when defining a function that takes no arguments: <code>fn foo:</code>)
are no longer ignored if the semantic analysis stage succeeds. (<a href="https://github.com/ethereum/fe/issues/535">#535</a>)</li>
<li>Fixed issue #531 by adding a <code>$</code> to the front of lowered tuple names. (<a href="https://github.com/ethereum/fe/issues/546">#546</a>)</li>
</ul>
<h3 id="internal-changes---for-fe-contributors-4"><a class="header" href="#internal-changes---for-fe-contributors-4">Internal Changes - for Fe Contributors</a></h3>
<ul>
<li>Implemented pretty printing of Fe AST. (<a href="https://github.com/ethereum/fe/issues/540">#540</a>)</li>
</ul>
<h2 id="080-alpha-haxonite-2021-08-31"><a class="header" href="#080-alpha-haxonite-2021-08-31">0.8.0-alpha "Haxonite" (2021-08-31)</a></h2>
<h3 id="features-9"><a class="header" href="#features-9">Features</a></h3>
<ul>
<li>
<p>Support quotes, tabs and carriage returns in string literals and otherwise
restrict string literals to the printable subset of the ASCII table. (<a href="https://github.com/ethereum/fe/issues/329">#329</a>)</p>
</li>
<li>
<p>The analyzer now uses a query-based system, which fixes some shortcomings of the previous implementation.</p>
<ul>
<li>Types can now refer to other types defined later in the file.
Example:</li>
</ul>
<pre><code>type Posts = Map<PostId, PostBody>
type PostId = u256
type PostBody = String<140>
</code></pre>
<ul>
<li>Duplicate definition errors now show the location of the original definition.</li>
<li>The analysis of each function, type definition, etc happens independently, so an error in one
doesn't stop the analysis pass. This means fe can report more user errors in a single run of the compiler. (<a href="https://github.com/ethereum/fe/issues/468">#468</a>)</li>
</ul>
</li>
<li>
<p>Function definitions are now denoted with the keyword fn instead of def. (<a href="https://github.com/ethereum/fe/issues/496">#496</a>)</p>
</li>
<li>
<p>Variable declarations are now preceded by the <code>let</code> keyword. Example: <code>let x: u8 = 1</code>. (<a href="https://github.com/ethereum/fe/issues/509">#509</a>)</p>
</li>
<li>
<p>Implemented support for numeric unary invert operator (<code>~</code>) (<a href="https://github.com/ethereum/fe/issues/526">#526</a>)</p>
</li>
</ul>
<h3 id="bugfixes-7"><a class="header" href="#bugfixes-7">Bugfixes</a></h3>
<ul>
<li>
<p>Calling <code>self.__init__()</code> now results in a nice error instead of a panic in the yul compilation stage. (<a href="https://github.com/ethereum/fe/issues/468">#468</a>)</p>
</li>
<li>
<p>Fixed an issue where certain expressions were not being moved to the correct location. (<a href="https://github.com/ethereum/fe/issues/493">#493</a>)</p>
</li>
<li>
<p>Fixed an issue with a missing return statement not properly detected.</p>
<p>Previous to this fix, the following code compiles but it should not:</p>
<pre><code>contract Foo:
pub fn bar(val: u256) -> u256:
if val > 1:
return 5
</code></pre>
<p>With this change, the compiler rightfully detects that the code is missing
a <code>return</code> or <code>revert</code> statement after the <code>if</code> statement since it is not
guaranteed that the path of execution always follows the arm of the <code>if</code> statement. (<a href="https://github.com/ethereum/fe/issues/497">#497</a>)</p>
</li>
<li>
<p>Fixed a bug in the analyzer which allowed tuple item accessor names with a leading 0,
resulting in an internal compiler error in a later pass. Example: <code>my_tuple.item001</code>.
These are now rejected with an error message. (<a href="https://github.com/ethereum/fe/issues/510">#510</a>)</p>
</li>
<li>
<p>Check call argument labels for function calls.</p>
<p>Previously the compiler would not check any labels that were used
when making function calls on <code>self</code> or external contracts.</p>
<p>This can be especially problematic if gives developers the impression
that they could apply function arguments in any order as long as they
are named which is <strong>not</strong> the case. </p>
<pre><code>contract Foo:
pub fn baz():
self.bar(val2=1, doesnt_even_exist=2)
pub fn bar(val1: u256, val2: u256):
pass
</code></pre>
<p>Code as the one above is now rightfully rejected by the compiler. (<a href="https://github.com/ethereum/fe/issues/517">#517</a>)</p>
</li>
</ul>
<h3 id="improved-documentation"><a class="header" href="#improved-documentation">Improved Documentation</a></h3>
<ul>
<li>
<p>Various improvements and bug fixes to both the content and layout of the specification. (<a href="https://github.com/ethereum/fe/issues/489">#489</a>)</p>
</li>
<li>
<p>Document all remaining statements and expressions in the spec.</p>
<p>Also added a CI check to ensure code examples in the documentation
are validated against the latest compiler. (<a href="https://github.com/ethereum/fe/issues/514">#514</a>)</p>
</li>
</ul>
<h3 id="internal-changes---for-fe-contributors-5"><a class="header" href="#internal-changes---for-fe-contributors-5">Internal Changes - for Fe Contributors</a></h3>
<ul>
<li>Separated Fe type traits between crates. (<a href="https://github.com/ethereum/fe/issues/485">#485</a>)</li>
</ul>
<h2 id="070-alpha-galaxite-2021-07-27"><a class="header" href="#070-alpha-galaxite-2021-07-27">0.7.0-alpha "Galaxite" (2021-07-27)</a></h2>
<h3 id="features-10"><a class="header" href="#features-10">Features</a></h3>
<ul>
<li>
<p>Enable the optimizer by default. The optimizer can still be disabled
by supplying <code>--optimize=false</code> as an argument. (<a href="https://github.com/ethereum/fe/issues/439">#439</a>)</p>
</li>