Language reference

Find a construct, its exact behavior and the corresponding implementation account. The specification defines source semantics. Reference C# illustrates implementations; the developer bridge highlights differences from C# and VB.NET.

What you need	Detailed reference
A keyword, operator, contextual name or API	Alphabetical lookup
Why source is invalid and how to repair its intent	Diagnostics and repairs
Source, literals, names and project declarations	Syntax and binding
Types, defaults, locals, actions and callable values	Types and actions
Generic declarations, constraints and typed construction	Generics and constraints
Classes, constructors, interfaces and class kinds	Objects and construction
Evaluation, select, contracts, patterns and lazy values	Expressions and checks
Optional work, lazy state, cached failures and recursive forcing	Lazy values and publication
Strict/Try sequence selection, indexing and maps	Collections and lookup
URI, HTML, XML, JSON and quoted-string content	Encoding for the destination
Receiver scopes, exceptions and disposal	Resources and errors
Await, task capture, owned work and cancellation	Async and concurrency
Handler identity, source replacement and observation lifetime	Events and subscriptions
CLR binding, attributes and service ownership	.NET contracts
Gate, consumption, text, sequences and service behavior	Standard-library contracts
Selected CLR declarations, source member types and export boundaries	Library API catalogue
Feature discovery, operations, wrappers and engine/asset boundaries	Adapter declarations
Evaluation, cleanup and coordination implementation cases	C# reference implementation
Queue, renderer and API application patterns	Customer showcase reference

Behavior at boundaries

These cases are useful when reviewing business logic or comparing it with a native .NET call. Follow the contract of the symbol actually bound, especially when a library method has a familiar name.

Boundary	DirectSharp contract	Details
Missing versus empty selection	Try selection returns nothing when no items are selected; valid strict zero selection is present empty	Sequence contracts
Source too short for a strict request	Deferred traversal can expose a prefix before the shortage fails; tolerant Try selection collects available values at the call	C# sequence patterns
Async result versus operation	Await a fresh call for its result, capture it with task_of, or launch it with run; bare awaitable calls are diagnosed	Async intent
Several steps per concurrent branch	Inline run blocks progress independently; return finishes one branch after cleanup	Inline branches
Forgotten captured operation	Warn on locally detectable abandonment; owned run work is joined automatically	Operation observation
Await and UI access	Ordinary await normally retains the UI context; ConfigureAwait(false) opts out rather than dispatching to it	Continuation context
Async and synchronous cleanup	The static disposable contract and action context select one route; successful authored cleanup is shared across both protocols	Resource lifetimes
Cleanup fails or overlaps	Authored cleanup rejects overlap and retains its original failure; imported types and Gate retain their own separate contracts	Authored cleanup
Reader row versus retained object	A current IDataRecord view changes as its reader advances; project independent values before retaining or parallelizing it	Consumable sources
Producer fails with queued work	An explicitly failed live wrapper drains buffered items, then reports the original failure; native channels retain native behavior	Live concurrent collections
Service names versus service keys	Source names ignore case; keyed service identity is exact and rejects a null key	Lookup signatures
Detach a handler during a raise	An already captured native invocation list can still deliver it; detachment does not cancel in-flight work	Event lifetime
Selected winner versus published result	A winner is still subject to owned joins and external causes recorded before publication	Concurrent outcomes