014 subflow transitive pure

✓ Passing This code compiles and runs correctly.

Code

// Layer 2 demonstration (positive case): a subflow dispatching ONLY
// into pure events should be transitively pure. Mirrors 410_016's
// negative case (subflow dispatching impure → transitively impure).
//
// Pairs with 410_016 to pin both directions of transitive propagation.

const std = @import("std");

// Pure operation
~event compute { x: i32 } -> i32

~[pure] proc compute|zig {
    return x * 2;
}

~event main {}

// Subflow dispatching pure event — should be transitively PURE
~compute(x: 21)

input.kz

Flows

flow ~compute click a branch to expand · @labels scroll to their anchor

compute (x: 21)

Test Configuration

MUST_RUN

Post-validation Script:

#!/bin/bash
# Verify: subflow dispatching only pure events is transitively pure.
#
# Re-pointed 2026-07-03: the serialized-AST Zig literal (backend.zig /
# program_ast.zig) is RETIRED — the backend loads program.ast.json at
# runtime, so that JSON is the serialized AST and the artifact to assert
# against. The old grep-the-Zig-literal form passed on stale artifacts
# only (the harness never cleaned program_ast.zig).

if [ ! -f "program.ast.json" ]; then
    echo "✗ program.ast.json not found"
    exit 1
fi

python3 - <<'EOF'
import json, sys
d = json.load(open('program.ast.json'))

def find(kind, name):
    for it in d['items']:
        if kind in it:
            v = it[kind]
            segs = (v.get('path') or {}).get('segments') or []
            if segs and segs[-1] == name:
                return v
    return None

def first_flow():
    for it in d['items']:
        if 'flow' in it:
            return it['flow']
    return None

def check(entity, label, field, want):
    if entity is None:
        print(f"✗ Could not find {label}")
        sys.exit(1)
    got = entity.get(field)
    if got is not want:
        print(f"✗ FAIL: {label} should have {field} = {str(want).lower()}, got {str(got).lower()}")
        sys.exit(1)

p = find('proc_decl', 'compute')
check(p, 'compute proc', 'is_pure', True)
print("✓ compute proc: is_pure = true")
check(p, 'compute proc', 'is_transitively_pure', True)
print("✓ compute proc: is_transitively_pure = true")
f = first_flow()
check(f, 'subflow', 'is_pure', True)
print("✓ subflow: is_pure = true (Layer 1 — composition is locally pure)")
check(f, 'subflow', 'is_transitively_pure', True)
print("✓ subflow: is_transitively_pure = true (dispatches only into pure events)")
print()
print("✓ Subflow correctly marked transitively pure when dispatching only pure events")
EOF
exit $?

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