[SP024] Implement `some` keyword #7229

ArielG-NV · 2025-05-24T00:44:20Z

Changes:

Add support for some keyword
- to support generics the following was changed: 1. unwrap SomeType before opening existentials 2. unwrap SomeType before applying substitutions
more dyn keyword validation (primarily varDecl related)
Most new code is for tests

Note about missing feature, generics inference:

The given code does not infer generics as of TOT. Due to this, this feature won't have tests for this functionality:

__generic<T : IArithmetic>
void logic1(out IFooGeneric<T> dataIn1)
{
    dataIn1 = StructForIFooGeneric<T>(0);
}

__generic<T : IArithmetic>
void logic2(inout IFooGeneric<T> dataIn1, IFooGeneric<T> dataIn2)
{
    dataIn1.setVal(dataIn2.getVal());
}

RWStructuredBuffer<int> buffer;

void computeMain()
{
    IFooGeneric<float> data1;
    IFooGeneric<float> data2 = StructForIFooGeneric<float>(1);
    logic1(data1);
    logic2(data1, data2);
    buffer[0] = int(data1.getVal() == 
                + data2.getVal());
}

Note about file-tree for tests added:

this will be changed in the next PR, the organization was temporary while the rest of the plan was being finalized.

Fixes: shader-slang#7146

…aces missing the keyword

Implement sp024 lang 2026

…support Format code for PR shader-slang#7172

…ement-SP024-dyn-support Regenerate command line reference for PR shader-slang#7172

… yet. re-organize the validation as per review, did not fix cmd-line-option yet, that is next.

…support Format code for PR shader-slang#7172

Implement sp024 dyn support

…ire AST This is not a full implementation, still requires: 1. clean up ==> SomeTypeDecl is used in an unclean way in many places 2. coerce types 3. proper and complete tests 4. return type checks 5. complete `dyn Type`, `SomeType`, and `UnboundSomeType` var assignment

slangbot · 2025-06-04T21:34:16Z

🌈 Formatted, please merge the changes from this PR

…-support Format code for PR shader-slang#7229

Another review is requested

kaizhangNV · 2025-06-05T03:51:11Z

source/slang/slang-ast-decl.h

@@ -137,6 +137,21 @@ class LetDecl : public VarDecl
    FIDDLE(...)
 };

+// Represents the type `SomeType<IFoo>`


Please update your comment to use the actual syntax.
e.g. represent some IFoo var; but it's used as in/inout parameter of a function, e.g.
void func(in some IFoo var); there the type must be a concrete type when the function is called.

UnboundSomeTypeDecl
represents some IFoo var; but it's only used as out function parameter, e.g.
void func(out some IFoo var); so var is unbounded some type, and it can be assigned by another some type variable.

The reason we use bound and unbound is to distinguished those two cases, as only unbounded some type variable can be assigned value.

kaizhangNV · 2025-06-05T04:00:02Z

source/slang/slang-check-conversion.cpp

+    // Manages coerce rules for `SomeTypeDecl` and `UnboundSomeTypeDecl`.
+    // Primarily this function diagnoses incorrect `SomeTypeDecl` coercing.
+    // To coerce this function unwraps the inner interface type of a `SomeTypeDecl`.
+    if (tryCoerceSomeType(site, toType, outToExpr, fromType, fromExpr, sink, outCost))


To keep the convention, can you make the if condition surround this function

if (isDeclRefTypeOf<SomeTypeDecl>(toType) || isDeclRefTypeOf<SomeTypeDecl>(fromType)) { return tryCoerceSomeType(...); }

kaizhangNV · 2025-06-05T04:02:17Z

source/slang/slang-check-conversion.cpp

+    // If we have a SomeType on RHS, we are only allowed to copy if LHS is `dyn`
+    if (auto someTypeDeclRef = isDeclRefTypeOf<SomeTypeDecl>(fromType))
+    {
+        if (isDynGivenType(toType))


if toType is not dyn, will it have diagnostics?

It will error.

More specifically:

implicit_conversion will error. This is because implicit conversion requires exactly the same type when resolving overloads through coerce (overloadContext.disallowNestedConversions), which is not possible with some type since all instances of some are different.

Explicit conversion works fine.

kaizhangNV · 2025-06-05T04:04:03Z