352 lines
12 KiB
Rust
352 lines
12 KiB
Rust
//! Disposable B-syntax experiment. This is not the production language.
|
|
//! All semantic checks are delegated to the real source3 compiler.
|
|
use oa_core::{
|
|
Project,
|
|
language::{self, TokenClass, TokenSpan},
|
|
source_project::{self, ProjectLimits, SourceBundle},
|
|
};
|
|
use std::collections::BTreeMap;
|
|
|
|
pub mod writeback;
|
|
|
|
#[derive(Debug, Clone)]
|
|
struct Record {
|
|
kind: String,
|
|
header: String,
|
|
alias: String,
|
|
fields: BTreeMap<String, String>,
|
|
endpoint_ports: Option<(String, String)>,
|
|
}
|
|
#[derive(Debug)]
|
|
enum Entry {
|
|
Text(String),
|
|
Record(Record),
|
|
}
|
|
|
|
/// Compile the complete B project after lowering its authored files to source3.
|
|
pub fn compile(bundle: &SourceBundle) -> Result<Project, String> {
|
|
let lowered = lower(bundle)?;
|
|
source_project::compile_bundle(&lowered, ProjectLimits::default())
|
|
.map(|result| result.decoded.project)
|
|
.map_err(|errors| format!("{errors:?}"))
|
|
}
|
|
|
|
pub fn lower(bundle: &SourceBundle) -> Result<SourceBundle, String> {
|
|
let mut units = BTreeMap::new();
|
|
let mut owners = BTreeMap::new();
|
|
for (path, source) in &bundle.files {
|
|
let entries = Parser::new(source)?
|
|
.unit(path == &bundle.entry)
|
|
.map_err(|error| format!("{path}: {error}"))?;
|
|
for entry in &entries {
|
|
if let Entry::Record(record) = entry
|
|
&& owners
|
|
.insert(record.alias.clone(), record.fields.get("parent").cloned())
|
|
.is_some()
|
|
{
|
|
return Err(format!("Duplicate declaration alias @{}", record.alias));
|
|
}
|
|
}
|
|
units.insert(path.clone(), entries);
|
|
}
|
|
let mut files = BTreeMap::new();
|
|
for (path, entries) in units {
|
|
let mut text = String::new();
|
|
for entry in entries {
|
|
match entry {
|
|
Entry::Text(raw) => {
|
|
text.push_str(&raw);
|
|
text.push('\n');
|
|
}
|
|
Entry::Record(mut record) => {
|
|
if let Some((source, target)) = &record.endpoint_ports {
|
|
for (field, port) in [("source", source), ("target", target)] {
|
|
let owner = owners
|
|
.get(port)
|
|
.and_then(|owner| owner.as_ref())
|
|
.ok_or_else(|| {
|
|
format!("Endpoint @{port} has no explicit function owner")
|
|
})?;
|
|
record.fields.insert(field.into(), owner.clone());
|
|
record
|
|
.fields
|
|
.insert(format!("{field}_port"), format!("@{port}"));
|
|
}
|
|
}
|
|
text.push_str(&record.header);
|
|
text.push_str(" {\n");
|
|
for (name, value) in record.fields {
|
|
text.push_str(&format!(" {name} {value};\n"));
|
|
}
|
|
text.push_str("}\n");
|
|
}
|
|
}
|
|
}
|
|
files.insert(path, text);
|
|
}
|
|
Ok(SourceBundle {
|
|
entry: bundle.entry.clone(),
|
|
files,
|
|
})
|
|
}
|
|
|
|
struct Parser<'a> {
|
|
source: &'a str,
|
|
tokens: Vec<TokenSpan>,
|
|
at: usize,
|
|
}
|
|
impl<'a> Parser<'a> {
|
|
fn new(source: &'a str) -> Result<Self, String> {
|
|
let tokens: Vec<_> = language::tokenize(source)
|
|
.into_iter()
|
|
.filter(|token| !matches!(token.class, TokenClass::Whitespace | TokenClass::Comment))
|
|
.collect();
|
|
if tokens.iter().any(|token| token.class == TokenClass::Error) {
|
|
return Err("Invalid lexical token".into());
|
|
}
|
|
Ok(Self {
|
|
source,
|
|
tokens,
|
|
at: 0,
|
|
})
|
|
}
|
|
fn peek(&self) -> &'a str {
|
|
self.tokens
|
|
.get(self.at)
|
|
.map_or("", |token| &self.source[token.span.start..token.span.end])
|
|
}
|
|
fn take(&mut self, expected: &str) -> Result<(), String> {
|
|
if self.peek() != expected {
|
|
return Err(format!(
|
|
"Expected {expected}, got {:?} at token {}",
|
|
self.peek(),
|
|
self.at
|
|
));
|
|
}
|
|
self.at += 1;
|
|
Ok(())
|
|
}
|
|
fn word(&mut self) -> Result<String, String> {
|
|
let token = self.tokens.get(self.at).ok_or("Unexpected end of input")?;
|
|
if !matches!(token.class, TokenClass::Identifier | TokenClass::Keyword) {
|
|
return Err(format!("Expected identifier, got {}", self.peek()));
|
|
}
|
|
let value = self.peek().to_owned();
|
|
self.at += 1;
|
|
Ok(value)
|
|
}
|
|
fn string(&mut self) -> Result<(), String> {
|
|
if self
|
|
.tokens
|
|
.get(self.at)
|
|
.is_none_or(|token| token.class != TokenClass::String)
|
|
{
|
|
return Err("Expected quoted string".into());
|
|
}
|
|
self.at += 1;
|
|
Ok(())
|
|
}
|
|
fn reference(&mut self) -> Result<String, String> {
|
|
self.take("@")?;
|
|
self.word()
|
|
}
|
|
fn slice(&self, start: usize, end: usize) -> String {
|
|
self.source[self.tokens[start].span.start..self.tokens[end - 1].span.end].to_owned()
|
|
}
|
|
fn value(&mut self) -> Result<String, String> {
|
|
let start = self.at;
|
|
let mut closers = Vec::new();
|
|
loop {
|
|
match self.peek() {
|
|
"" => return Err("Unterminated field".into()),
|
|
";" if closers.is_empty() => break,
|
|
"{" => closers.push("}"),
|
|
"[" => closers.push("]"),
|
|
"}" | "]" => {
|
|
closers
|
|
.pop()
|
|
.filter(|closing| *closing == self.peek())
|
|
.ok_or("Unbalanced field")?;
|
|
}
|
|
_ => {}
|
|
}
|
|
if closers.len() > 64 {
|
|
return Err("Field nesting exceeds experiment limit".into());
|
|
}
|
|
self.at += 1;
|
|
}
|
|
if self.at == start {
|
|
return Err("Missing field value".into());
|
|
}
|
|
let value = self.slice(start, self.at);
|
|
self.take(";")?;
|
|
Ok(value)
|
|
}
|
|
fn unit(mut self, entry: bool) -> Result<Vec<Entry>, String> {
|
|
let mut out = Vec::new();
|
|
if entry {
|
|
let start = self.at;
|
|
self.take("arcadia")?;
|
|
self.take("3")?;
|
|
self.take(";")?;
|
|
self.take("project")?;
|
|
self.word()?;
|
|
self.string()?;
|
|
self.take("id")?;
|
|
self.string()?;
|
|
self.take("{")?;
|
|
out.push(Entry::Text(self.slice(start, self.at)));
|
|
}
|
|
while !self.peek().is_empty() && !(entry && self.peek() == "}") {
|
|
if self.peek() == "include" || (entry && self.peek() == "description") {
|
|
let start = self.at;
|
|
self.at += 1;
|
|
self.value()?;
|
|
out.push(Entry::Text(self.slice(start, self.at)));
|
|
} else {
|
|
self.record(None, &mut out, 0)?;
|
|
}
|
|
}
|
|
if entry {
|
|
self.take("}")?;
|
|
out.push(Entry::Text("}".into()));
|
|
}
|
|
if !self.peek().is_empty() {
|
|
return Err("Unexpected trailing input".into());
|
|
}
|
|
Ok(out)
|
|
}
|
|
fn record(
|
|
&mut self,
|
|
owner: Option<(&str, &str)>,
|
|
out: &mut Vec<Entry>,
|
|
depth: usize,
|
|
) -> Result<String, String> {
|
|
if depth > 32 {
|
|
return Err("Ownership nesting exceeds experiment limit".into());
|
|
}
|
|
let start = self.at;
|
|
let kind = self.word()?;
|
|
let alias = self.word()?;
|
|
if kind != "node" {
|
|
self.string()?;
|
|
}
|
|
self.take("id")?;
|
|
self.string()?;
|
|
let header = self.slice(start, self.at);
|
|
let mut record = Record {
|
|
kind: kind.clone(),
|
|
header,
|
|
alias: alias.clone(),
|
|
fields: BTreeMap::new(),
|
|
endpoint_ports: None,
|
|
};
|
|
if matches!(kind.as_str(), "input" | "output") {
|
|
let Some((owner, "sa_function")) = owner else {
|
|
return Err("Typed function port shorthand requires an SA function owner".into());
|
|
};
|
|
self.take("items")?;
|
|
let items = self.value()?;
|
|
record.kind = "sa_port".into();
|
|
record.header = record.header.replacen(&kind, "sa_port", 1);
|
|
record.fields.insert("parent".into(), format!("@{owner}"));
|
|
let (variant, field) = if kind == "input" {
|
|
("FunctionInput", "incoming_items")
|
|
} else {
|
|
("FunctionOutput", "outgoing_items")
|
|
};
|
|
record.fields.insert(
|
|
"contract".into(),
|
|
format!("{{ {variant} {{ {field} {items}; }}; }}"),
|
|
);
|
|
} else if kind == "functional_exchange" && self.peek() == "from" {
|
|
self.take("from")?;
|
|
let source = self.reference()?;
|
|
self.take("to")?;
|
|
let target = self.reference()?;
|
|
self.take("items")?;
|
|
let items = self.value()?;
|
|
record.fields.insert("items".into(), items);
|
|
record.endpoint_ports = Some((source, target));
|
|
if self.peek() == "{" {
|
|
self.body(&mut record, out, depth)?;
|
|
}
|
|
for field in ["source", "target", "source_port", "target_port"] {
|
|
if record.fields.contains_key(field) {
|
|
return Err(format!(
|
|
"Contradictory shorthand/explicit endpoint field {field}"
|
|
));
|
|
}
|
|
}
|
|
} else {
|
|
self.body(&mut record, out, depth)?;
|
|
if let Some((owner, _)) = owner {
|
|
if !kind.starts_with("oa_") && !kind.starts_with("sa_") {
|
|
return Err("Only elements may use semantic ownership nesting".into());
|
|
}
|
|
let inferred = format!("@{owner}");
|
|
if record
|
|
.fields
|
|
.get("parent")
|
|
.is_some_and(|parent| parent != &inferred)
|
|
{
|
|
return Err(format!("Contradictory parent for @{alias}"));
|
|
}
|
|
record.fields.insert("parent".into(), inferred);
|
|
}
|
|
}
|
|
out.push(Entry::Record(record));
|
|
Ok(alias)
|
|
}
|
|
fn body(
|
|
&mut self,
|
|
record: &mut Record,
|
|
out: &mut Vec<Entry>,
|
|
depth: usize,
|
|
) -> Result<(), String> {
|
|
self.take("{")?;
|
|
while self.peek() != "}" {
|
|
if self.peek().is_empty() {
|
|
return Err("Unterminated declaration".into());
|
|
}
|
|
let nested = self.peek().starts_with("oa_")
|
|
|| self.peek().starts_with("sa_")
|
|
|| matches!(self.peek(), "input" | "output");
|
|
if nested {
|
|
self.record(Some((&record.alias, &record.kind)), out, depth + 1)?;
|
|
continue;
|
|
}
|
|
let field = self.word()?;
|
|
if record.fields.contains_key(&field) {
|
|
return Err(format!("Duplicate field {field} on @{}", record.alias));
|
|
}
|
|
let value = if field == "steps" && self.peek() == "{" {
|
|
if !matches!(
|
|
record.kind.as_str(),
|
|
"oa_scenario" | "sa_scenario" | "oa_process" | "sa_functional_chain"
|
|
) {
|
|
return Err("Ordered steps require a scenario/process/chain".into());
|
|
}
|
|
self.take("{")?;
|
|
let mut steps = Vec::new();
|
|
while self.peek() != "}" {
|
|
if !matches!(self.peek(), "oa_occurrence" | "sa_occurrence") {
|
|
return Err("Ordered steps contain occurrence declarations only".into());
|
|
}
|
|
steps.push(format!(
|
|
"@{}",
|
|
self.record(Some((&record.alias, &record.kind)), out, depth + 1)?
|
|
));
|
|
}
|
|
self.take("}")?;
|
|
self.take(";")?;
|
|
format!("[{}]", steps.join(", "))
|
|
} else {
|
|
self.value()?
|
|
};
|
|
record.fields.insert(field, value);
|
|
}
|
|
self.take("}")
|
|
}
|
|
}
|