From afc1d9b18cd08836ddedf5247ec7abb6671ad3e2 Mon Sep 17 00:00:00 2001 From: Alex Bethel Date: Thu, 22 Jul 2021 22:08:04 -0500 Subject: [PATCH] Use coercion in BFF argument passing --- src/variables.rs | 67 ++++++------------------------------------------ 1 file changed, 8 insertions(+), 59 deletions(-) diff --git a/src/variables.rs b/src/variables.rs index d9bc7bd..7f3184c 100644 --- a/src/variables.rs +++ b/src/variables.rs @@ -54,66 +54,15 @@ pub enum Value { } impl Value { - /// Write an AbleScript value to a Brainfuck input stream. This - /// should generally only be called on `Write`rs that cannot fail, - /// e.g., `Vec`, because any IO errors will cause a panic. - /// - /// The mapping from values to encodings is as follows, where all - /// multi-byte integers are little-endian: - /// - /// | AbleScript representation | Brainfuck representation | - /// |---------------------------|-------------------------------------------------------------| - /// | Nul | `00` | - /// | Str | `01` [length, 4 bytes] [string, \[LENGTH\] bytes, as UTF-8] | - /// | Int | `02` [value, 4 bytes] | - /// | Bool | `03` `00` false, `03` `01` true. | - /// | Abool | `04` `00` never, `04` `01` always, `04` `02` sometimes. | - /// | Brainfuck Functio | `05` `00` [length, 4 bytes] [source code, \[LENGTH\] bytes] | - /// | AbleScript Functio | `05` `01` (todo, not yet finalized or implemented) | - /// - /// The existing mappings should never change, as they are - /// directly visible from Brainfuck code and modifying them would - /// break a significant amount of AbleScript code. If more types - /// are added in the future, they should be assigned the remaining - /// discriminant bytes from 06..FF. + /// Write an AbleScript value to a Brainfuck input stream by + /// coercing the value to an integer, then truncating that integer + /// to a single byte, then writing that byte. This should only be + /// called on `Write`rs that cannot fail, e.g., `Vec`, because + /// any IO errors will cause a panic. pub fn bf_write(&self, stream: &mut impl Write) { - match self { - Value::Nul => stream.write_all(&[0]), - Value::Str(s) => stream - .write_all(&[1]) - .and_then(|_| stream.write_all(&(s.len() as u32).to_le_bytes())) - .and_then(|_| stream.write_all(&s.as_bytes())), - Value::Int(v) => stream - .write_all(&[2]) - .and_then(|_| stream.write_all(&v.to_le_bytes())), - Value::Bool(b) => stream - .write_all(&[3]) - .and_then(|_| stream.write_all(&[*b as _])), - Value::Abool(a) => stream.write_all(&[4]).and_then(|_| { - stream.write_all(&[match *a { - Abool::Never => 0, - Abool::Sometimes => 2, - Abool::Always => 1, - }]) - }), - Value::Functio(f) => stream.write_all(&[5]).and_then(|_| match f { - Functio::BfFunctio { - instructions, - tape_len: _, - } => { - // NOTE(Alex): Tape length should maybe be taken - // into account here. - stream - .write_all(&[0]) - .and_then(|_| stream.write_all(&(instructions.len() as u32).to_le_bytes())) - .and_then(|_| stream.write_all(&instructions)) - } - Functio::AbleFunctio { params: _, body: _ } => { - todo!() - } - }), - } - .expect("Failed to write to Brainfuck input"); + stream + .write_all(&[self.clone().into_i32() as u8]) + .expect("Failed to write to Brainfuck input"); } /// Coerce a value to an integer.