Add a function `OptionFromPtr` that constructs an `Option` from a
pointer. The function signature is: `OptionFromPtr : *A -> Option[A]`.
This utility has proven useful in the taproot-assets project.
This adds the ContextGuard struct from the taproot-assets repository
that has been in use there for a while.
The context guard allows for easy creation of contexts that depend on a
central wait group and quit channel.
A context can either be created with a timeout and quit, meaning it will
cancel either on reaching the timeout or when the central quit channel
is closed.
Or a context can be created to block and use a timeout, meaning it will
_not_ cancel on quit but rather block the shutdown until it is completed
(or times out).
The third way is to create a context that just cancels on quit with no
timeout.
The package provides type GoroutineManager which is used to launch goroutines
until context expires or the manager is stopped. Stop method blocks until all
started goroutines stop.
Original code by Andras https://go.dev/play/p/HhRpE-K2lA0
Adjustments and tests by Boris.
This commit adds an immutable Filter method to the linked List API.
This is useful because there are several instances wherein we iterate
through the linked List and only process a subset of it in some way
or another.
In this commit we opt to make the internal response channel fully
private and instead expose methods for doing resolution. This
prevents internal implementation details from leaking a little bit
better than the previous iteration.
It is common throughout the codebase to send data to a remote
goroutine for processing. Typically, along with the data we are
processing, we also send a one-shot channel where we intend to
listen for the response. This type encapsulates that pattern.
`NewResult` makes it easy to wrap a normal function call in a result
value.
`Err` can be used to check the error case of the result without
unpacking the entire thing.
`AndThen2` allows a caller to compose a function on two results values,
with the closure only executing if both values are non-error.
In this commit, we add a new result type, which is just Either[A, error]. This is useful as we can always pass around/accept a single value. We add an Unpack() method which is the most idiomatic way of handling errors in Go, as we revert back to (A, error) when necessary.
In the year of our lord 2024 we should not be writing for loops
for standard operations. Here we introduce named slice operations
not found in the golang slices package. Note all these functions
are pure.
In this commit, we add two new methods that simplify usage of an
handling a value wrapped in an Option. Thes methods allow a caller to
force the nil/None check up front, and either obtain the value, or fail
the current execution or test.
This should replace most usages of `UnsafeFromSome` where ever used
today.
