### DMASM Error Type Examples

Source: https://context7.com/willox/dmasm/llms.txt

Demonstrates instantiation of various error types from dmasm for assembly, disassembly, and compilation. CompileError handling shows matching specific error variants.

```rust
use dmasm::assembler::AssembleError;
use dmasm::disassembler::DisassembleError;
use dmasm::compiler::CompileError;

// AssembleError variants
let _ = AssembleError::ProcNotFound("/proc/missing".into());
let _ = AssembleError::TypeNotFound("/datum/nope".into());
let _ = AssembleError::InvalidVariableName;

// DisassembleError variants — all carry byte offset context
let _ = DisassembleError::UnknownOpcode { offset: 0x0C, opcode: 0xDEAD };
let _ = DisassembleError::InvalidString  { offset: 0x04, id: 9999 };
let _ = DisassembleError::InvalidProc   { offset: 0x08, id: 1234 };
let _ = DisassembleError::UnexpectedEnd;

// CompileError — wraps dreammaker parse errors
let result = dmasm::compiler::compile_expr("a +* b", &["a", "b"]);
match result {
    Err(CompileError::ParseError(e))              => eprintln!("parse: {}", e),
    Err(CompileError::UnsupportedBuiltin { proc }) => eprintln!("builtin: {}", proc),
    Err(CompileError::ExpectedLValue)             => eprintln!("not an l-value"),
    Err(e)                                         => eprintln!("{}", e),
    Ok(_)                                          => {}
}
```

--------------------------------

### Implementing AssembleEnv for BYOND String Pool

Source: https://context7.com/willox/dmasm/llms.txt

Provides an example implementation of the `AssembleEnv` trait for a `DmbEnv` struct, which wraps a BYOND .dmb string pool. This allows bridging DMASM strings to integer indices. Requires `dmasm::assembler` import.

```rust
use dmasm::assembler::{AssembleEnv, AssembleError};

/// Example: wraps a BYOND .dmb string pool
struct DmbEnv {
    string_pool: Vec<String>,
    var_names:   Vec<String>,
    proc_paths:  Vec<String>,
}

impl AssembleEnv for DmbEnv {
    fn get_string_index(&mut self, data: &[u8]) -> Option<u32> {
        let s = String::from_utf8_lossy(data).into_owned();
        if let Some(i) = self.string_pool.iter().position(|x| x == &s) {
            return Some(i as u32);
        }
        self.string_pool.push(s);
        Some(self.string_pool.len() as u32 - 1)
    }

    fn get_variable_name_index(&mut self, name: &[u8]) -> Option<u32> {
        let n = String::from_utf8_lossy(name).into_owned();
        self.var_names.iter().position(|x| x == &n).map(|i| i as u32)
    }

    fn get_proc_index(&mut self, path: &str) -> Option<u32> {
        self.proc_paths.iter().position(|x| x == path).map(|i| i as u32)
    }

    fn get_type(&mut self, _path: &str) -> Option<(u8, u32)> {
        // Return (type_tag, type_data) from the .dmb type table
        None // not supported in this example
    }
}
```

--------------------------------

### Implementing DisassembleEnv for BYOND Index Resolution

Source: https://context7.com/willox/dmasm/llms.txt

Shows an example implementation of the `DisassembleEnv` trait for a `DmbDisEnv` struct, which mirrors `AssembleEnv`. This allows converting numeric indices in bytecode back into human-readable strings. Requires `dmasm::disassembler` import.

```rust
use dmasm::disassembler::{DisassembleEnv};

struct DmbDisEnv {
    string_pool: Vec<Vec<u8>>,
    var_names:   Vec<Vec<u8>>,
    proc_paths:  Vec<String>,
    type_table:  std::collections::HashMap<(u32, u32), Vec<u8>>,
}

impl DisassembleEnv for DmbDisEnv {
    fn get_string_data(&mut self, index: u32) -> Option<Vec<u8>> {
        self.string_pool.get(index as usize).cloned()
    }

    fn get_variable_name(&mut self, index: u32) -> Option<Vec<u8>> {
        self.var_names.get(index as usize).cloned()
    }

    fn get_proc_name(&mut self, index: u32) -> Option<String> {
        self.proc_paths.get(index as usize).cloned()
    }

    fn value_to_string_data(&mut self, tag: u32, data: u32) -> Option<Vec<u8>> {
        // Resolve type-path values (mobs, objs, datums, etc.)
        self.type_table.get(&(tag, data)).cloned()
    }
}
```

--------------------------------

### Build and Format DMASM Nodes in Rust

Source: https://context7.com/willox/dmasm/llms.txt

Demonstrates how to manually construct `Node` elements, which represent comments, labels, or instructions in DMASM. It also shows how to render these nodes into human-readable DMASM text using the `format` helper.

```rust
use dmasm::{Node, Instruction, assembler, disassembler, format, format_disassembly};
use dmasm::disassembler::DebugData;

// Build nodes by hand
let nodes: Vec<Node> = vec![
    Node::Comment(" simple addition".into()),
    Node::Instruction(Instruction::PushInt(10), ()),
    Node::Instruction(Instruction::PushInt(32), ()),
    Node::Instruction(Instruction::Add, ()),
    Node::Instruction(Instruction::Ret, ()),
];

// Render to DMASM text
let text = format(&nodes);
assert!(text.contains("PushInt 10"));
assert!(text.contains("Add"));

// Strip debug data (no-op for () data)
let stripped: Vec<Node> = nodes.into_iter().map(|n| n.strip_debug_data()).collect();
```

--------------------------------

### Assemble Nodes to Bytecode

Source: https://context7.com/willox/dmasm/llms.txt

Converts a slice of `Node`s into a `Vec<u32>` bytecode stream. Requires an `AssembleEnv` implementation to map string literals, variable names, and proc paths to their runtime indices. Label forward-references are resolved in a second pass.

```rust
use dmasm::{Node, Instruction};
use dmasm::operands::{Label, Variable, DMString};
use dmasm::assembler::{assemble, AssembleEnv, AssembleError};

struct RuntimeEnv {
    strings: std::collections::HashMap<Vec<u8>, u32>,
}

impl AssembleEnv for RuntimeEnv {
    fn get_string_index(&mut self, data: &[u8]) -> Option<u32> {
        Some(*self.strings.entry(data.to_vec()).or_insert_with(|| self.strings.len() as u32))
    }
    fn get_variable_name_index(&mut self, name: &[u8]) -> Option<u32> { Some(0) }
    fn get_proc_index(&mut self, _path: &str) -> Option<u32> { None } // no procs needed here
    fn get_type(&mut self, _path: &str) -> Option<(u8, u32)> { None }
}

let nodes: Vec<Node> = vec![
    Node::Label("Loop".into()),
    Node::Instruction(Instruction::GetVar(Variable::Local(0)), ()),
    Node::Instruction(Instruction::PushInt(0), ()),
    Node::Instruction(Instruction::Tg, ()),
    Node::Instruction(Instruction::JzLoop(Label("Exit".into())), ()),
    Node::Instruction(Instruction::PreDec(Variable::Local(0)), ()),
    Node::Instruction(Instruction::JmpLoop(Label("Loop".into())), ()),
    Node::Label("Exit".into()),
    Node::Instruction(Instruction::End, ()),
];

let mut env = RuntimeEnv { strings: Default::default() };
match assemble(&nodes, &mut env) {
    Ok(bytecode) => println!("{} u32 words emitted", bytecode.len()),
    Err(AssembleError::ProcNotFound(p)) => eprintln!("proc not found: {}", p),
    Err(AssembleError::TypeNotFound(t)) => eprintln!("type not found: {}", t),
    Err(e) => eprintln!("error: {:?}", e),
}

```

--------------------------------

### `Instruction` Enum — Full Opcode Table

Source: https://context7.com/willox/dmasm/llms.txt

Provides a reference for all available DM opcodes within the `Instruction` enum, detailing their variants and usage.

```APIDOC
## `Instruction` Enum — Full Opcode Table

The `Instruction` enum has one variant per DM opcode (`0x00`–`0x18C` plus `0x1337`/`0x1338` for auxtools). Each variant implements `assemble`, `disassemble`, and `serialize` automatically via the `instructions!` macro, as well as `Display` (which calls `serialize`).

```rust
use dmasm::Instruction;
use dmasm::operands::{Label, Variable, Value, DMString, Proc};

// Stack / arithmetic
let push = Instruction::PushInt(42);
let add  = Instruction::Add;
let ret  = Instruction::Ret;
let end  = Instruction::End;

// Control flow
let jmp  = Instruction::Jmp(Label("MyLabel".into()));
let jz   = Instruction::Jz(Label("MyLabel".into()));
let jnz  = Instruction::JnzLoop(Label("MyLabel".into())); // loop-safe variant

// Variable access
let get  = Instruction::GetVar(Variable::Src);
let set  = Instruction::SetVar(Variable::Local(0));
let aug  = Instruction::AugAdd(Variable::Local(1));

// Call instructions
let call = Instruction::CallGlob(2, Proc("/proc/my_proc".into()));
let call_dyn = Instruction::CallName(3); // dynamic proc call by name

// Push a hardcoded DM value
let push_null = Instruction::PushVal(Value::Null);
let push_num  = Instruction::PushVal(Value::Number(3.14));
let push_str  = Instruction::PushVal(Value::DMString(DMString(b"hello".to_vec())));
let push_path = Instruction::PushVal(Value::Path("/mob/player".into()));

// Debug info
let dbg_file = Instruction::DbgFile(DMString(b"main.dm".to_vec()));
let dbg_line = Instruction::DbgLine(42);

// Display (serialize) any instruction
println!("{}", push);     // PushInt 42
println!("{}", call);     // CallGlob 2 /proc/my_proc
println!("{}", push_str); // PushVal "hello"
```
```

--------------------------------

### Display DMASM Instructions

Source: https://context7.com/willox/dmasm/llms.txt

Demonstrates the creation and display (serialization) of various `Instruction` enum variants. Each variant represents a DM opcode.

```rust
use dmasm::Instruction;
use dmasm::operands::{Label, Variable, Value, DMString, Proc};

// Stack / arithmetic
let push = Instruction::PushInt(42);
let add  = Instruction::Add;
let ret  = Instruction::Ret;
let end  = Instruction::End;

// Control flow
let jmp  = Instruction::Jmp(Label("MyLabel".into()));
let jz   = Instruction::Jz(Label("MyLabel".into()));
let jnz  = Instruction::JnzLoop(Label("MyLabel".into())); // loop-safe variant

// Variable access
let get  = Instruction::GetVar(Variable::Src);
let set  = Instruction::SetVar(Variable::Local(0));
let aug  = Instruction::AugAdd(Variable::Local(1));

// Call instructions
let call = Instruction::CallGlob(2, Proc("/proc/my_proc".into()));
let call_dyn = Instruction::CallName(3); // dynamic proc call by name

// Push a hardcoded DM value
let push_null = Instruction::PushVal(Value::Null);
let push_num  = Instruction::PushVal(Value::Number(3.14));
let push_str  = Instruction::PushVal(Value::DMString(DMString(b"hello".to_vec())));
let push_path = Instruction::PushVal(Value::Path("/mob/player".into()));

// Debug info
let dbg_file = Instruction::DbgFile(DMString(b"main.dm".to_vec()));
let dbg_line = Instruction::DbgLine(42);

// Display (serialize) any instruction
println!("{}", push);     // PushInt 42
println!("{}", call);     // CallGlob 2 /proc/my_proc
println!("{}", push_str); // PushVal "hello"

```

--------------------------------

### Parse DMASM Text and Assemble Bytecode in Rust

Source: https://context7.com/willox/dmasm/llms.txt

Shows how to parse DMASM source text into a `Vec<Node>` using `dmasm::parser::parse` and then assemble these nodes into raw bytecode using `dmasm::assembler::assemble`. Requires a custom implementation of `AssembleEnv` to resolve identifiers.

```rust
use dmasm::assembler::{self, AssembleEnv, AssembleError};

// Minimal AssembleEnv implementation for testing
struct MyEnv;
impl AssembleEnv for MyEnv {
    fn get_string_index(&mut self, _data: &[u8]) -> Option<u32> { Some(42) }
    fn get_variable_name_index(&mut self, _name: &[u8]) -> Option<u32> { Some(43) }
    fn get_proc_index(&mut self, _path: &str) -> Option<u32> { Some(44) }
    fn get_type(&mut self, _path: &str) -> Option<(u8, u32)> { Some((0x09, 0x01)) }
}

// parse is re-exported through the crate but lives in parser
let source = r#" 
; Set up debug info
DbgFile "main.dm"
DbgLine 5

; Conditional jump example
PushInt 1
Jz Done
PushInt 99
Ret
Done:
PushInt 0
Ret
"#;

// Parse text -> nodes
let nodes = dmasm::parser::parse(source).expect("parse failed");

// Assemble nodes -> bytecode
let mut env = MyEnv;
let bytecode: Vec<u32> = assembler::assemble(&nodes, &mut env).expect("assemble failed");
println!("bytecode words: {}", bytecode.len());
```

--------------------------------

### Compile DM Expression to Nodes and Assemble

Source: https://context7.com/willox/dmasm/llms.txt

Compile a DM source expression string into a `Vec<Node<()>>` using `compile_expr`. The output nodes are ready for assembly. Requires implementing `AssembleEnv`.

```rust
use dmasm::compiler::{compile_expr, CompileError};
use dmasm::assembler::{assemble, AssembleEnv};
use dmasm::format;

struct TestEnv;
impl AssembleEnv for TestEnv {
    fn get_string_index(&mut self, _: &[u8]) -> Option<u32> { Some(1) }
    fn get_variable_name_index(&mut self, _: &[u8]) -> Option<u32> { Some(2) }
    fn get_proc_index(&mut self, _: &str) -> Option<u32> { Some(3) }
    fn get_type(&mut self, _: &str) -> Option<(u8, u32)> { Some((0x09, 1)) }
}

// Compile "a * 2 + b" with two parameters a and b
match compile_expr("a * 2 + b", &["a", "b"]) {
    Ok(nodes) => {
        println!("---" --- DMASM ---\n{}", format(&nodes));
        let bytecode = assemble(&nodes, &mut TestEnv).unwrap();
        println!("bytecode: {:x?}", bytecode);
    }
    Err(CompileError::ParseError(e)) => eprintln!("DM parse error: {}", e),
    Err(CompileError::UnsupportedBuiltin { proc }) => eprintln!("unsupported: {}", proc),
    Err(e) => eprintln!("compile error: {}", e),
}

// Null-safe field access
let nodes = compile_expr("a?.b++", &["a"]).unwrap();
println!("{}", format(&nodes));

```

--------------------------------

### Format DMASM Nodes to Plain Text

Source: https://context7.com/willox/dmasm/llms.txt

Use the `format` function to render a slice of `Node<D>` as plain DMASM text. This includes comments, labels, and instructions with their operands.

```rust
use dmasm::{Node, Instruction, format};
use dmasm::operands::{Label, Variable};

let nodes: Vec<Node> = vec![
    Node::Comment(" countdown".into()),
    Node::Label("Loop".into()),
    Node::Instruction(Instruction::PostDec(Variable::Local(0)), (),
    Node::Instruction(Instruction::GetVar(Variable::Local(0)), ()),
    Node::Instruction(Instruction::JnzLoop(Label("Loop".into())), ()),
    Node::Instruction(Instruction::End, ()),
];

let text = format(&nodes);
println!("{}", text);

```

--------------------------------

### `format` — Plain Node Formatter

Source: https://context7.com/willox/dmasm/llms.txt

Renders a slice of `Node<D>` as plain DMASM text, preserving comments, labels, and instructions with their operands.

```APIDOC
## `format` — Plain Node Formatter

Renders any `&[Node<D>]` (regardless of debug data type) as plain DMASM text, reproducing comments, label definitions, and instructions with their operands.

```rust
use dmasm::{Node, Instruction, format};
use dmasm::operands::{Label, Variable};

let nodes: Vec<Node> = vec![
    Node::Comment(" countdown".into()),
    Node::Label("Loop".into()),
    Node::Instruction(Instruction::PostDec(Variable::Local(0)), (..)),
    Node::Instruction(Instruction::GetVar(Variable::Local(0)), (..)),
    Node::Instruction(Instruction::JnzLoop(Label("Loop".into())), (..)),
    Node::Instruction(Instruction::End, (..)),
];

let text = format(&nodes);
println!("{}", text);
// ; countdown
// Loop:
// PostDec local(0)
// GetVar local(0)
// JnzLoop LAB_0000   <- (label name set at construction time)
// End
```
```

--------------------------------

### Format Disassembly Output

Source: https://context7.com/willox/dmasm/llms.txt

Renders a slice of `Node<DebugData>` into a multi-column string for debugger-style output. Includes a cursor marker, word offset, raw bytecode, and mnemonic with operands. Can optionally display a cursor at a specific word offset.

```rust
use dmasm::{Node, Instruction, format_disassembly};
use dmasm::disassembler::{disassemble, DebugData};

// (reusing MyDisEnv from above)
let bytecode: Vec<u32> = vec![
    0x84, 42,         // DbgFile "string_42"
    0x85, 7,          // DbgLine 7
    0x50, 100,        // PushInt 100
    0x12,             // Ret
];

let mut env = MyDisEnv;
let (nodes, _) = disassemble(&bytecode, &mut env);

// No cursor
let text = format_disassembly(&nodes, None);
println!("{}", text);

// With cursor pointing at word offset 4 (the PushInt instruction)
let text_cursor = format_disassembly(&nodes, Some(4));
println!("{}", text_cursor);
// Outputs:
//  0000:  00000084 0000002A  DbgFile "string_42"
//  0002:  00000085 00000007  DbgLine 7
// >0004:  00000050 00000064  PushInt 100
//  0006:  00000012           Ret

```

--------------------------------

### Disassemble Bytecode to Nodes

Source: https://context7.com/willox/dmasm/llms.txt

Converts a bytecode slice into `Node`s, optionally returning a `DisassembleError`. Labels are automatically inserted before jump targets. `DebugData` is included for each instruction, providing word offset and original bytecode.

```rust
use dmasm::{Node, format_disassembly};
use dmasm::disassembler::{disassemble, DisassembleEnv, DisassembleError, DebugData};

struct MyDisEnv;
impl DisassembleEnv for MyDisEnv {
    fn get_string_data(&mut self, index: u32) -> Option<Vec<u8>> {
        Some(format!("string_{}", index).into_bytes())
    }
    fn get_variable_name(&mut self, index: u32) -> Option<Vec<u8>> {
        Some(format!("var_{}", index).into_bytes())
    }
    fn get_proc_name(&mut self, index: u32) -> Option<String> {
        Some(format!("/proc/func{}", index))
    }
    fn value_to_string_data(&mut self, tag: u32, data: u32) -> Option<Vec<u8>> {
        Some(format!("/datum/tag{}data{}", tag, data).into_bytes())
    }
}

// Bytecode for: PushInt 5; Ret; End  (opcodes 0x50 0x05 0x12 0x00)
let bytecode: Vec<u32> = vec![0x50, 5, 0x12, 0x00];

let mut env = MyDisEnv;
let (nodes, err) = disassemble(&bytecode, &mut env);

if let Some(e) = err {
    eprintln!("disassembly stopped early: {:?}", e);
}

// Print with offsets and hex (cursor at offset 2 shows '>' marker)
println!("{}", format_disassembly(&nodes, Some(2)));

// Expected output:
//  0000:  00000050 00000005  PushInt 5
// >0002:  00000012           Ret
//  0003:  00000000           End

```

--------------------------------

### `compiler::compile_expr` — DM Expression to Nodes

Source: https://context7.com/willox/dmasm/llms.txt

Compiles a DM source expression string into a `Vec<Node<()>>`. The output nodes prepare the stack for assembly.

```APIDOC
## `compiler::compile_expr` — DM Expression to Nodes

Compiles a DM source expression string directly into a `Vec<Node<()>>`. Parameters are named positionally; the output nodes push the result and parameter values onto the stack then emit `NewList` + `Ret`, ready for assembly. Uses the `dreammaker` crate for parsing.

```rust
use dmasm::compiler::{compile_expr, CompileError};
use dmasm::assembler::{assemble, AssembleEnv};
use dmasm::format;

struct TestEnv;
impl AssembleEnv for TestEnv {
    fn get_string_index(&mut self, _: &[u8]) -> Option<u32> { Some(1) }
    fn get_variable_name_index(&mut self, _: &[u8]) -> Option<u32> { Some(2) }
    fn get_proc_index(&mut self, _: &str) -> Option<u32> { Some(3) }
    fn get_type(&mut self, _: &str) -> Option<(u8, u32)> { Some((0x09, 1)) }
}

// Compile "a * 2 + b" with two parameters a and b
match compile_expr("a * 2 + b", &["a", "b"]) {
    Ok(nodes) => {
        println!("---
DMASM ---
{}", format(&nodes));
        let bytecode = assemble(&nodes, &mut TestEnv).unwrap();
        println!("bytecode: {:x?}", bytecode);
    }
    Err(CompileError::ParseError(e)) => eprintln!("DM parse error: {}", e),
    Err(CompileError::UnsupportedBuiltin { proc }) => eprintln!("unsupported: {}", proc),
    Err(e) => eprintln!("compile error: {}", e),
}

// Null-safe field access
let nodes = compile_expr("a?.b++", &["a"]).unwrap();
println!("{}", format(&nodes));
```
```

--------------------------------

### Variable Operand Encoding in DMASM

Source: https://context7.com/willox/dmasm/llms.txt

Demonstrates various ways to use the `Variable` enum to encode DM access modifiers, including simple variables, chained fields, and nested variants. Ensure `dmasm::operands` is imported.

```rust
use dmasm::operands::{Variable, DMString, Proc};

let v_src    = Variable::Src;
let v_usr    = Variable::Usr;
let v_dot    = Variable::Dot;
let v_arg0   = Variable::Arg(0);
let v_local2 = Variable::Local(2);
let v_global = Variable::Global(DMString(b"my_global".to_vec()));
let v_field  = Variable::Field(DMString(b"x".to_vec()));

// Chained field: set cache to src, then access field "name"
let v_chain = Variable::SetCache(
    Box::new(Variable::Src),
    Box::new(Variable::Field(DMString(b"name".to_vec()))),
);

// initial(src.health)
let v_initial = Variable::Initial(Box::new(Variable::SetCache(
    Box::new(Variable::Src),
    Box::new(Variable::Field(DMString(b"health".to_vec()))),
)));

// Static proc reference
let v_sproc = Variable::StaticProc(Proc("/datum/proc/on_hit".into()));
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.