Struct Context 

pub struct Context { /* private fields */ }

Context for evaluation of a resolved µcad file.

The context is used to store the current state of the evaluation.

A context consists of the following members:

• A symbol table (SymbolTable) with symbols stored by QualifiedName and a Stack.
• A diagnostic handler (DiagHandler) that accumulates evaluation errors for later output.
• One output channel (Output) where __builtin::print writes it’s output to while evaluation.

All these internal structures can be accessed by several implemented traits.

Implementations

impl Context

pub fn new( root: Identifier, symbols: SymbolMap, sources: Sources, output: Box<dyn Output>, ) -> Self

Create a new context from a source file.

Arguments

• root: Root symbol.
• builtin: The builtin library.
• search_paths: Paths to search for external libraries (e.g. the standard library).
• output: Output channel to use.

pub fn current_symbol(&self) -> Symbol

Current symbol, panics if there no current symbol.

pub fn from_source( root: impl AsRef<Path> + Debug, builtin: Symbol, search_paths: &[PathBuf], ) -> EvalResult<Self>

Create a new context from a source file.

Arguments

• root: Path to the root file to load.
• builtin: The builtin library.
• search_paths: Paths to search for external libraries (e.g. the standard library).

pub fn output(&self) -> Option<String>

Access captured output.

pub fn print(&mut self, what: String)

Print for __builtin::print.

pub fn locate(&self, referrer: &impl SrcReferrer) -> EvalResult<String>

Get the source code location of the given referrer as string (e.g. /path/to/file.µcad:52:1).

pub fn source_code(&self, referrer: &impl SrcReferrer) -> EvalResult<String>

Get the original source code of the given referrer.

pub fn eval(&mut self) -> EvalResult<Model>

Evaluate context into a value.

pub fn root(&self) -> &Symbol

Peek into root node for testing.

pub fn scope<T>( &mut self, stack_frame: StackFrame, f: impl FnOnce(&mut Context) -> T, ) -> T

Run the closure f within the given stack_frame.

pub fn set_importers(&mut self, importers: ImporterRegistry)

Set importers.

pub fn exporters(&self) -> &ExporterRegistry

All registered exporters.

pub fn set_exporters(&mut self, exporters: ExporterRegistry)

Set exporters.

pub fn search_paths(&self) -> &Vec<PathBuf>

Return search paths of this context.

pub fn get_property(&self, id: &Identifier) -> EvalResult<Value>

Get property from current model.

pub fn init_property(&self, id: Identifier, value: Value) -> EvalResult<()>

Initialize a property.

Returns error if there is no model or the property has been initialized before.

pub fn is_init(&mut self) -> bool

Return if the current frame is an init frame.

impl Context

pub fn use_symbol( &mut self, visibility: Visibility, name: &QualifiedName, id: Option<Identifier>, ) -> EvalResult<Symbol>

use symbol in context

pub fn use_symbols_of( &mut self, visibility: Visibility, name: &QualifiedName, ) -> EvalResult<Symbol>

use all symbols of given module in context

Trait Implementations

impl Default for Context

fn default() -> Self

Returns the “default value” for a type.

impl Diag for Context

fn fmt_diagnosis(&self, f: &mut dyn Write) -> Result

Pretty print all errors.

fn error_count(&self) -> u32

Return number of occurred errors.

fn error_lines(&self) -> HashSet<usize>

Return all lines with errors

fn warning_lines(&self) -> HashSet<usize>

Return all lines with warnings

fn write_diagnosis(&self, w: &mut dyn Write) -> Result<()>

Pretty write all errors into a file.

fn diagnosis(&self) -> String

Get pretty printed errors as string.

fn has_errors(&self) -> bool

Returns true if there are errors.

impl Display for Context

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl ExporterAccess for Context

fn exporter_by_id(&self, id: &Id) -> Result<Rc<dyn Exporter>, ExportError>

Get exporter by id.

fn exporter_by_filename( &self, filename: &Path, ) -> Result<Rc<dyn Exporter>, ExportError>

Get exporter by filename.

fn find_exporter( &self, filename: &Path, id: &Option<Id>, ) -> Result<Rc<dyn Exporter>, ExportError>

Find an exporter by filename, or by id.

impl GetSourceByHash for Context

fn get_by_hash(&self, hash: u64) -> ResolveResult<Rc<SourceFile>>

Find a project file by it’s hash value.

impl Grant<AssignmentStatement> for Context

fn grant(&mut self, statement: &AssignmentStatement) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<Attribute> for Context

fn grant(&mut self, statement: &Attribute) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<ExpressionStatement> for Context

fn grant(&mut self, statement: &ExpressionStatement) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<FunctionDefinition> for Context

fn grant(&mut self, statement: &FunctionDefinition) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<IfStatement> for Context

fn grant(&mut self, statement: &IfStatement) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<InitDefinition> for Context

fn grant(&mut self, statement: &InitDefinition) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<Marker> for Context

fn grant(&mut self, statement: &Marker) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<ModuleDefinition> for Context

fn grant(&mut self, statement: &ModuleDefinition) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<ReturnStatement> for Context

fn grant(&mut self, statement: &ReturnStatement) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<UseStatement> for Context

fn grant(&mut self, statement: &UseStatement) -> EvalResult<()>

Check if given statement T is granted within the current context

impl Grant<WorkbenchDefinition> for Context

fn grant(&mut self, statement: &WorkbenchDefinition) -> EvalResult<()>

Check if given statement T is granted within the current context

impl ImporterRegistryAccess for Context

type Error = EvalError

Error type.

fn import( &mut self, arg_map: &Tuple, search_paths: &[PathBuf], ) -> Result<Value, Self::Error>

Import a value from an argument map

impl Locals for Context

fn set_local_value(&mut self, id: Identifier, value: Value) -> EvalResult<()>

Set/add a named local value to current locals.

fn get_local_value(&self, id: &Identifier) -> EvalResult<Value>

Get a named local value from locals.

fn open(&mut self, frame: StackFrame)

Don’t use this function directly.

fn close(&mut self)

Close scope (stack pop).

fn fetch(&self, id: &Identifier) -> EvalResult<Symbol>

Fetch a local variable from current stack frame.

fn get_model(&self) -> EvalResult<Model>

Get a property value from current model.

fn current_name(&self) -> QualifiedName

Return qualified name of current module or workbench.

impl Lookup for Context

fn lookup(&mut self, name: &QualifiedName) -> EvalResult<Symbol>

Lookup for local or global symbol by qualified name.

impl PushDiag for Context

fn push_diag(&mut self, diag: Diagnostic) -> EvalResult<()>

Push a diagnostic message (must be implemented).

fn trace(&mut self, src: &impl SrcReferrer, message: String)

Push new trace message.

fn info(&mut self, src: &impl SrcReferrer, message: String)

Push new informative message.

fn warning( &mut self, src: &impl SrcReferrer, error: impl Error + 'static, ) -> EvalResult<()>

Push new warning.

fn error( &mut self, src: &impl SrcReferrer, error: impl Error + 'static, ) -> EvalResult<()>

Push new error.