{
  "schema": "1",
  "generated": "2026-10-24",
  "commit": "c7be3aafe528591074991042e447d2a979e3de5c",
  "sources": {
    "corpus": "benchmarks/real_scripts/scripts",
    "report": "benchmarks/real_scripts/REPORT.md"
  },
  "summary": {
    "scripts": 39,
    "total_fences": 51,
    "unique_codes": [
      "PS1001",
      "PS1003",
      "PS1103",
      "PS1104",
      "PS1105",
      "PS1106",
      "PS1202",
      "PS2001",
      "PS2002",
      "PS2003",
      "PS2004"
    ]
  },
  "causes": [
    {
      "id": "stdlib-surface",
      "title": "Standard library surface",
      "description": "Calls to standard library modules in the closed import table whose specific function or method is not yet lowered to native IR.",
      "fences": [
        {
          "module": "dataclasses",
          "construct": "`dataclasses.asdict`",
          "code": "PS2001",
          "diagnostic": "dataclasses.asdict is not in the lowered subset of dataclasses"
        },
        {
          "module": "itertools",
          "construct": "`itertools.product`",
          "code": "PS2001",
          "diagnostic": "itertools.product is not in the lowered subset of itertools"
        },
        {
          "module": "os",
          "construct": "`os.system`",
          "code": "PS2001",
          "diagnostic": "os.system is not in the lowered subset of os"
        },
        {
          "module": "pathlib",
          "construct": "`p.is_dir`",
          "code": "PS2001",
          "diagnostic": "p.is_dir is not in the lowered subset of pathlib"
        },
        {
          "module": "pathlib",
          "construct": "`p.is_file`",
          "code": "PS2001",
          "diagnostic": "p.is_file is not in the lowered subset of pathlib"
        },
        {
          "module": "random",
          "construct": "`random.sample`",
          "code": "PS2001",
          "diagnostic": "random.sample is not in the lowered subset of random"
        },
        {
          "module": "subprocess",
          "construct": "`subprocess.Popen`",
          "code": "PS2001",
          "diagnostic": "subprocess.Popen is not in the lowered subset of subprocess"
        },
        {
          "module": "time",
          "construct": "`time.process_time`",
          "code": "PS2001",
          "diagnostic": "time.process_time is not in the lowered subset of time"
        },
        {
          "module": "zipfile",
          "construct": "`zipfile.ZipFile`",
          "code": "PS2001",
          "diagnostic": "zipfile.ZipFile is not in the lowered subset of zipfile"
        }
      ]
    },
    {
      "id": "imports",
      "title": "Closed import table",
      "description": "Standard library and external modules that are not yet in the closed import table. Importing them halts compilation with a fence.",
      "fences": [
        {
          "module": "pylong",
          "construct": "import pylong",
          "code": "PS2002",
          "diagnostic": "_pylong is not in the closed import table"
        },
        {
          "module": "pyperf",
          "construct": "import pyperf",
          "code": "PS2002",
          "diagnostic": "pyperf is not in the closed import table"
        },
        {
          "module": "sqlite3",
          "construct": "import sqlite3",
          "code": "PS2002",
          "diagnostic": "sqlite3 is not in the closed import table"
        }
      ]
    },
    {
      "id": "call-table",
      "title": "Call signatures and keyword arguments",
      "description": "Calls that pass keyword arguments, unsupported argument counts, or non-scalar arguments halt at the call table.",
      "fences": [
        {
          "module": "argparse",
          "construct": "`argparse` option/default",
          "code": "PS2003",
          "diagnostic": "argparse.add_argument keyword nargs is not lowered"
        },
        {
          "module": "argparse",
          "construct": "call arity",
          "code": "PS2003",
          "diagnostic": "ArgParser.add_mutually_exclusive_group is not lowered"
        },
        {
          "module": "builtins",
          "construct": "`abs()` on non-number",
          "code": "PS2003",
          "diagnostic": "abs is lowered for int and float"
        },
        {
          "module": "builtins",
          "construct": "`input()` with prompt",
          "code": "PS2003",
          "diagnostic": "input expects 0 argument(s)"
        },
        {
          "module": "builtins",
          "construct": "`open(newline=...)`",
          "code": "PS2003",
          "diagnostic": "open keyword newline is not lowered; open lowers encoding= only"
        },
        {
          "module": "builtins",
          "construct": "`print(list)`",
          "code": "PS2003",
          "diagnostic": "print is lowered for str, int, float, bool, and bytes values, not list; wrap it in str(...)"
        },
        {
          "module": "builtins",
          "construct": "`zip()` with >2 args",
          "code": "PS2003",
          "diagnostic": "zip takes 2 lists"
        },
        {
          "module": "builtins",
          "construct": "call to unlowered function",
          "code": "PS2002",
          "diagnostic": "call to findPassword is not lowered"
        },
        {
          "module": "builtins",
          "construct": "keyword arguments",
          "code": "PS2003",
          "diagnostic": "keyword arguments are not lowered"
        },
        {
          "module": "hashlib",
          "construct": "`hashlib.sha256()`",
          "code": "PS2003",
          "diagnostic": "hashlib.sha256 expects 1 argument(s)"
        },
        {
          "module": "sys",
          "construct": "`sys.exit()`",
          "code": "PS2003",
          "diagnostic": "sys.exit expects 1 argument(s)"
        }
      ]
    },
    {
      "id": "inference",
      "title": "Type annotations and inference",
      "description": "pyscriptc requires type annotations on function parameters, return types, and local variable declarations that cannot be inferred from literals or lowered calls.",
      "fences": [
        {
          "module": "builtins",
          "construct": "forward class reference",
          "code": "PS1105",
          "diagnostic": "the forward reference 'Config' is not lowered"
        },
        {
          "module": "builtins",
          "construct": "function without return annotation",
          "code": "PS1001",
          "diagnostic": "read needs a return annotation"
        },
        {
          "module": "builtins",
          "construct": "local variable without annotation",
          "code": "PS1001",
          "diagnostic": "state needs an annotation before use"
        },
        {
          "module": "builtins",
          "construct": "name read after unannotated assignment",
          "code": "PS2002",
          "diagnostic": "had_error is not a local or parameter"
        },
        {
          "module": "builtins",
          "construct": "parameter without annotation",
          "code": "PS1001",
          "diagnostic": "parameter chars needs an annotation"
        },
        {
          "module": "collections",
          "construct": "`collections.defaultdict`",
          "code": "PS1103",
          "diagnostic": "DefaultDict is not a lowered type in the IR"
        },
        {
          "module": "json",
          "construct": "unlowered type annotation",
          "code": "PS1001",
          "diagnostic": "json.load needs the result annotation"
        },
        {
          "module": "random",
          "construct": "unlowered type annotation",
          "code": "PS1106",
          "diagnostic": "the annotation random.Random names a type that is not lowered"
        },
        {
          "module": "typing",
          "construct": "`typing.Any`",
          "code": "PS1104",
          "diagnostic": "Any is not a lowered type in the IR"
        },
        {
          "module": "typing",
          "construct": "unlowered type annotation",
          "code": "PS1001",
          "diagnostic": "a lambda needs a Callable[[args], ret] annotation"
        }
      ]
    },
    {
      "id": "statements",
      "title": "Statements and language constructs",
      "description": "Statement forms, unpack patterns, and language constructs that have not yet been lowered.",
      "fences": [
        {
          "module": "builtins",
          "construct": "`data.sort()`",
          "code": "PS2001",
          "diagnostic": "call of attribute is not lowered (data.sort)"
        },
        {
          "module": "builtins",
          "construct": "`files.remove()`",
          "code": "PS2001",
          "diagnostic": "call of attribute is not lowered (files.remove)"
        },
        {
          "module": "builtins",
          "construct": "`global` statement",
          "code": "PS2002",
          "diagnostic": "global pw is not a module slot"
        },
        {
          "module": "builtins",
          "construct": "`zip()` of nested list",
          "code": "PS2002",
          "diagnostic": "zip() of list[list[str]] is not lowered"
        },
        {
          "module": "builtins",
          "construct": "dataclass bool field",
          "code": "PS2002",
          "diagnostic": "bool fields are not lowered"
        },
        {
          "module": "builtins",
          "construct": "for over list[Path]",
          "code": "PS2002",
          "diagnostic": "for over list[Path] is not lowered"
        },
        {
          "module": "builtins",
          "construct": "infinite iterators are not lowered",
          "code": "PS2001",
          "diagnostic": "infinite iterators are not lowered"
        },
        {
          "module": "builtins",
          "construct": "nested tuple unpack in loop",
          "code": "PS2002",
          "diagnostic": "for unpacks flat names"
        },
        {
          "module": "builtins",
          "construct": "non-constant module assignment",
          "code": "PS2002",
          "diagnostic": "a module assignment must be a constant"
        },
        {
          "module": "datetime",
          "construct": "`DateTime.strftime`",
          "code": "PS2001",
          "diagnostic": "DateTime.strftime is not a method"
        },
        {
          "module": "pathlib",
          "construct": "`Path.endswith`",
          "code": "PS2001",
          "diagnostic": "Path.endswith is not a method"
        }
      ]
    },
    {
      "id": "classes",
      "title": "Classes and object model",
      "description": "Class attributes, method declarations, and class decorators outside the lowered object model.",
      "fences": [
        {
          "module": "builtins",
          "construct": "class attribute access",
          "code": "PS2001",
          "diagnostic": "Namespace.files is not a field"
        }
      ]
    },
    {
      "id": "operators",
      "title": "Operators",
      "description": "Operators applied to unlowered operand type combinations halt with an operator fence.",
      "fences": [
        {
          "module": "builtins",
          "construct": "operator on unlowered types",
          "code": "PS2004",
          "diagnostic": "Add on None and opt_str is not lowered"
        }
      ]
    },
    {
      "id": "checker",
      "title": "Type checking",
      "description": "The type-checker preflight rejects type mismatches between values and declared annotations before lowering begins.",
      "fences": [
        {
          "module": "builtins",
          "construct": "type annotation mismatch",
          "code": "PS1003",
          "diagnostic": "open path is str"
        },
        {
          "module": "os",
          "construct": "type annotation mismatch",
          "code": "PS1003",
          "diagnostic": "os.walk top is str"
        },
        {
          "module": "pathlib",
          "construct": "type annotation mismatch",
          "code": "PS1003",
          "diagnostic": "posixpath.join arguments are str"
        },
        {
          "module": "subprocess",
          "construct": "type annotation mismatch",
          "code": "PS1003",
          "diagnostic": "subprocess takes a list of str"
        }
      ]
    },
    {
      "id": "reflection",
      "title": "Dynamic reflection",
      "description": "Dynamic argument unpacking and keyword forwarding that cannot be lowered natively route to the island runtime.",
      "fences": [
        {
          "module": "builtins",
          "construct": "`**kwargs` forwarding",
          "code": "PS1202",
          "diagnostic": "update declares **kwargs: keyword forwarding (**kwargs) collects keyword arguments into a mapping at run time, and the native lane keeps no keyword mapping for a parameter; this code routes to the island lane (requires libpython); typed idiom: PEP 692 Unpack[TypedDict] declares the accepted keyword keys"
        }
      ]
    }
  ]
}