// SPDX-License-Identifier: MPL-2.0

// AffineScript Standard Library - Effect Declarations

// Core IO effect - file and console operations

effect IO;

// State effect - mutable references

effect Mut;

// Exception effect - panics and error handling

effect Throws;

// Async effect - promise / suspend semantics. The Deno-ESM backend

// emits native `async`/`await` and the Thenable extern ABI (issue

// #103); the v1 effect-row registry (#196) already reserves `Async`.

// Declared here so the stdlib effect-declarations file is coherent

// with the registry (echidna#62). Tracking-only in v1 (no handler).

effect Async;

// Built-in IO operations

extern fn print(s: String) -> Unit / IO;

extern fn println(s: String) -> Unit / IO;

extern fn read_line() -> String / IO;

extern fn read_file(path: String) -> String / IO;

extern fn write_file(path: String, content: String) -> Unit / IO;

// Built-in State operations

// `make_ref` (not `ref`) because `ref` is a reserved ownership keyword;

// see #135 keyword-as-identifier slice.

extern fn make_ref<T>(x: T) -> Ref<T> / Mut;

extern fn get<T>(r: Ref<T>) -> T / Mut;

extern fn set<T>(r: Ref<T>, x: T) -> Unit / Mut;

// Built-in Exception operations

extern fn panic(msg: String) -> Never / Throws;

extern fn error<T>(msg: String) -> T / Throws;

// Pure operations (no effects)

extern fn int_to_string(n: Int) -> String;

extern fn string_to_int(s: String) -> Option<Int>;

extern fn string_length(s: String) -> Int;

// `string_concat` removed (STDLIB-04c, Refs #330): the canonical surface

// for string concatenation is the `++` operator, lowered directly in

// `Value.binop_string` (interp) and `__as_concat` (Deno codegen). The

// extern was declared but never wired in any backend nor called from

// any stdlib/test/fixture file — dead surface.