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Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::DelegateInvoke_ActionVoid_IL_Runtime   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func runCallback(x: int) -> int {
    var result = 0
    let cb = func(v: int) { result = v * 2 }
    cb(x)
    return result
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::DeriveEquality_RefData_WorksWithDifferentInstances   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

derive equality
class Config {
    name: string
    port: int

    init(name: string, port: int) {
        self.name = name
        self.port = port
    }
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Emit_LambdaWithTupleReturnType   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace T
func run() {
    var tasks = List<Task<(List<string>, List<string>)>>()
    tasks.Add(Task.Run(func() -> (List<string>, List<string>) { return (List<string>(), List<string>()) }))
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::EntryPoint_Transpiler_EmitsMain   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func main() {
    var x = 42
}

Runs `run` → 2

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Event_Subscribe_ObservableCollectionCollectionChanged   topic: core   status: verified
// verified behavior: Test.run(...) == 2

namespace Test

func run() -> int {
    var fired = 0
    let coll = ObservableCollection<int>()
    coll.CollectionChanged += func(sender: object, args: NotifyCollectionChangedEventArgs) -> void {
        fired = fired + 1
    }
    coll.Add(10)
    coll.Add(20)
    return fired
}

Runs `always42` → 42

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::ExpressionBodied_SimpleReturn   topic: core   status: verified
// verified behavior: Test.always42(...) == 42

namespace Test

func double(x: int) -> int = x * 2
func negate(x: int) -> int = 0 - x
func always42() -> int = 42

Runs `run` → 21

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::ExpressionBodiedMethodInRefData   topic: core   status: verified
// verified behavior: Test.run(...) == 21

namespace Test

class Box {
    value: int
    init(v: int) { self.value = v }
    func get() -> int = self.value
    func doubled() -> int = self.value * 2
}

func run() -> int {
    let b = Box(7)
    return b.get() + b.doubled()
}

Runs `run` → 3

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Extension_LinqCount_OnList   topic: core   status: verified
// verified behavior: Test.run(...) == 3

namespace Test

func run() -> int {
    let nums = List<int>()
    nums.Add(1)
    nums.Add(2)
    nums.Add(3)
    return nums.Count()
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::ExternalCall_ConsoleWriteLine_IL   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func main() {
    Console.WriteLine("hello")
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::FunctionPointer_Ldftn_EmitsCorrectOpcode   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func double(x: int) -> int {
    return x * 2
}

func getDoublePtr() -> int {
    let ptr = &double
    return 0
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::FunctionPointer_TranspilerEmitsDelegateStar   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func double(x: int) -> int {
    return x * 2
}

func getPtr() -> int {
    let ptr = &double
    return 0
}

Runs `run` → 2

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::GenericCall_EnumerableCountOnList   topic: core   status: verified
// verified behavior: Test.run(...) == 2

namespace Test

func run() -> int {
    let nums = List<int>()
    nums.Add(10)
    nums.Add(20)
    return Enumerable.Count<int>(nums)
}

Runs `run` → 6

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::GenericCall_InferenceStillWorks   topic: core   status: verified
// verified behavior: Test.run(...) == 6

namespace Test

func run() -> int {
    let nums = List<int>()
    nums.Add(1)
    nums.Add(2)
    nums.Add(3)
    return nums.Sum()
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::GenericConstructorCall_List_ParsesCorrectly   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func make() -> int {
    let items = List<string>()
    return 0
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::GenericExternalType_Runtime_ListAdd   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func run() -> int {
    var count = 0
    count = 3
    return count
}

Runs `run` → 0

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::GenericTypeWithTupleArg_NoStackOverflow   topic: core   status: verified
// verified behavior: Test.run(...) == 0

namespace Test

func run() -> int {
    var xs = List<(int, int)>()
    return xs.Count
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::IL_Diagnostics_UnresolvedType_ReportsError   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func broken(x: Nonexistent) -> int {
    return 0
}

Runs `run` → 99

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Indexer_ListGetSet_RoundTrip   topic: core   status: verified
// verified behavior: Test.run(...) == 99

namespace Test

func run() -> int {
    let list = List<int>()
    list.Add(10)
    list.Add(20)
    list.Add(30)
    list[1] = 99
    return list[1]
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Init_Constructor_IL_Runtime   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

class Point {
    x: int
    y: int

    init(px: int, py: int) {
        x = px
        y = py
    }
}

func getX() -> int {
    let p = Point { x: 0, y: 0 }
    return p.x
}

ILEmitterTests__LetElse_ReturnsOnNull

core runnable verified

Runs `runFound` → "found"

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::LetElse_ReturnsOnNull   topic: core   status: verified
// verified behavior: Test.runFound(...) == "found"

namespace Test

func tryFind(key: string) -> string? {
    if key == "a" {
        return "found"
    }
    return nil
}

func run() -> string {
    let value = tryFind("b") else {
        return "default"
    }
    return value
}

func runFound() -> string {
    let value = tryFind("a") else {
        return "default"
    }
    return value
}

Runs `first` → 42

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::ListLiteral_IntElements   topic: core   status: verified
// verified behavior: Test.first(...) == 42

namespace Test

func count() -> int {
    let xs = [10, 20, 30]
    return xs.Count
}

func first() -> int {
    let xs = [42, 99]
    return xs[0]
}

Runs `joined` → "hello"

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::ListLiteral_StringElements   topic: core   status: verified
// verified behavior: Test.joined(...) == "hello"

namespace Test

func joined() -> string {
    let xs = ["hello", "world"]
    return xs[0]
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::MultiFile_DistinctNamespaces_CoexistInOneAssembly   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Alpha

func a() -> int { return 1 }

Runs `run` → 0

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::NestedGenericWithTupleArg_NoStackOverflow   topic: core   status: verified
// verified behavior: Test.run(...) == 0

namespace Test

func run() -> int {
    var xs = List<(List<int>, List<int>)>()
    return xs.Count
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::NoAwait_Binder_HasAwaitIsFalse   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func add(a: int, b: int) -> int {
    return a + b
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Nullable_NilReturn_ReferenceType_Runtime   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func tryFind(s: string) -> string? {
    return nil
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Nullable_NilReturn_ValueType_Runtime   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func tryParse(s: string) -> int? {
    return nil
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Nullable_ValueType_ResolvesToSystemNullable   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func maybe(x: int?) -> int {
    return 0
}

Runs `fallback` → "hello"

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::NullCoalescing_StringFallback   topic: core   status: verified
// verified behavior: Test.fallback(...) == "hello"

namespace Test

func fallback(s: string) -> string {
    return s ?? "default"
}

Runs `safeLen` → 5

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::NullConditional_ChainedWithCoalescing   topic: core   status: verified
// verified behavior: Test.safeLen(...) == 5

namespace Test

func safeLen(s: string) -> int {
    let result = s ?? ""
    return result.Length
}

func withCoalesce(s: string) -> string {
    return s ?? "none"
}

Runs `run` → -1

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Out_IntTryParse_Failure   topic: core   status: verified
// verified behavior: Test.run(...) == -1

namespace Test

func run() -> int {
    if int.TryParse("not a number", out var n) {
        return n
    }
    return -1
}

Runs `run` → 42

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Out_IntTryParse_Success   topic: core   status: verified
// verified behavior: Test.run(...) == 42

namespace Test

func run() -> int {
    if int.TryParse("42", out var n) {
        return n
    }
    return -1
}

Runs `run` → "hello world"

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Params_StringFormat_NoExtraArgs   topic: core   status: verified
// verified behavior: Test.run(...) == "hello world"

namespace Test

func run() -> string {
    return string.Format("hello {0}", "world")
}

Runs `run` → "1 + 2 = 3"

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Params_StringFormat_TwoArgs   topic: core   status: verified
// verified behavior: Test.run(...) == "1 + 2 = 3"

namespace Test

func run() -> string {
    return string.Format("{0} + {1} = {2}", 1, 2, 3)
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Parse_ForTupleDestructuring   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace T
func run() {
    let results = List<(int, int)>()
    for (a, b) in results {
        let x = a + b
    }
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Parse_ImportStaticAndArrowLambda   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace T
using static "System.Math"

func run() -> double {
    return Max(1.0, ((x) => x + 2.0)(3.0))
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Parse_LambdaWithComplexGenericReturnType   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace T
func run() {
    var xs = List<Task<(List<string>, List<string>)>>()
    xs.Add(Task.Run(func() -> (List<string>, List<string>) { return (List<string>(), List<string>()) }))
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Parse_NullConditionalAndCoalesceInTernary   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace T
func run() {
    let s: string = nil
    let x = s?.Length ?? 0
    let y = x > 0 ? s : "default"
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Parse_TryCatchWithTypedBinding   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace T
func run() {
    try {
        let x = 1
    } catch (Exception ex) {
        let msg = ex.Message
    }
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Parse_TupleTypeInGeneric   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

func test() -> int {
    var tasks = List<Task<(int, string)>>()
    return tasks.Count
}

Runs `make` → "hello"

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::PositionalClass_IsCaptureHeader   topic: core   status: verified
// verified behavior: Test.make(...) == "hello"

namespace Test

class Label(text: string, size: int) {
    func getText() -> string {
        return text
    }
}

func make() -> string {
    let l = Label("hello", 12)
    return l.getText()
}

Runs `run` → 3

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Property_GetFromBclObject_ListCount   topic: core   status: verified
// verified behavior: Test.run(...) == 3

namespace Test

func run() -> int {
    let list = List<int>()
    list.Add(1)
    list.Add(2)
    list.Add(3)
    return list.Count
}

Runs `run` → 5

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Property_GetFromBclObject_StringLength   topic: core   status: verified
// verified behavior: Test.run(...) == 5

namespace Test

func run() -> int {
    let s = "hello"
    return s.Length
}

Runs `go` → 25

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Protocol_AcrossFiles_DeclaredInA_ImplInB_UsedInC   topic: core   status: verified
// verified behavior: Test.go(...) == 25

namespace Test

interface IShape {
    func area() -> int
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Protocol_EmitsInterfaceType   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

interface IDrawable {
    func draw(x: int) -> string
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::Protocol_VirtualDispatch_IL_Runtime   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

interface ISpeaker {
    func speak() -> string
}

class Dog : ISpeaker {
    name: string
}

func (d: Dog) speak() -> string {
    return "woof"
}

func announce(s: ISpeaker) -> string {
    return s.speak()
}

Compiles

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::ProtocolType_ResolvesInMethodSignature   topic: core   status: verified
// compiles cleanly (no auto-run claim was extracted)

namespace Test

interface IWidget {
    func render() -> string
}

func display(w: IWidget) -> int {
    return 0
}

Runs `test` → 2

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::RefData_ExprBodiedMethod   topic: core   status: verified
// verified behavior: Test.test(...) == 2

namespace Test

class Bag {
    items: List<int>

    init() {
        self.items = List<int>()
    }

    func count() -> int = self.items.Count

    func add(x: int) {
        self.items.Add(x)
    }
}

func test() -> int {
    let b = Bag()
    b.add(10)
    b.add(20)
    return b.count()
}

Runs `run` → 3

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::RefDataMethods_BasicInstanceMethod   topic: core   status: verified
// verified behavior: Test.run(...) == 3

namespace Test

class Counter {
    value: int

    init() {
        self.value = 0
    }

    func inc() {
        self.value += 1
    }

    func get() -> int = self.value
}

func run() -> int {
    let c = Counter()
    c.inc()
    c.inc()
    c.inc()
    return c.get()
}

Runs `run` → "world"

// E# — a verified example from the E# language corpus (CLR language; .es, not ECMAScript).
// provenance: ILEmitterTests.cs::RefDataMethods_PubMethod   topic: core   status: verified
// verified behavior: Test.run(...) == "world"

namespace Test

class Greeter {
    name: string

    init(n: string) {
        self.name = n
    }

    pub func greet() -> string = self.name
}

func run() -> string {
    let g = Greeter("world")
    return g.greet()
}