General Information

	Eli: Translator Construction Made Easy
	Global Index
	Frequently Asked Questions
	Typical Eli Usage Errors

Tutorials

	Quick Reference Card
	Guide For new Eli Users
	Release Notes of Eli
	Tutorial on Name Analysis
	Tutorial on Scope Graphs
	Tutorial on Type Analysis
	Typical Eli Usage Errors

Reference Manuals

	User Interface
	Eli products and parameters
	LIDO Reference Manual
	Typical Eli Usage Errors

Libraries

	Eli library routines
	Specification Module Library

Translation Tasks

	Lexical analysis specification
	Syntactic Analysis Manual
	Computation in Trees

Tools

	LIGA Control Language
	Debugging Information for LIDO
	Graphical ORder TOol

FunnelWeb User's Manual

	Pattern-based Text Generator
	Property Definition Language
	Operator Identification Language
	Tree Grammar Specification Language
	Command Line Processing
	COLA Options Reference Manual

Generating Unparsing Code

Monitoring a Processor's Execution

Administration

System Administration Guide

Tutorial on Name Analysis

Insertion of Scopes into the Environment Hierarchy

We now demonstrate how scopes obtained from object properties are inserted into the environment hierarchy given by the syntactically nested ranges. For this purpose we extend our module example.

We introduce a with statement that allows the components of a module to be used without qualification in the WithBody. (This construct is similar to the with statement in Pascal, where record variables are used instead of the module identifiers discussed here. It directly corresponds to the use construct in Ada.)

ScopeInsert.con[25]==

Statement:      'with' WithClause 'do' WithBody.
WithClause:     ModUseIdent.
WithBody:       Statement.

This macro is attached to a product file.

The WithBody is a special kind of range: The scope rules for our with statement require that the scope of the module stated by the ModUseIdent is inserted in the environment hierarchy between the scope of the WithBody and the environment formed by the range nest that encloses the with statement. I.e. a definition in a range enclosing the with statement may be hidden by a definition of the module; those definitions may be hidden within the WithBody. (In the case of our language the WithBody may not directly contain declarations, although deeper nested Blocks may contain such declarations.)

We use another library module (see Inheritance of Scopes of Specification Module Library: Name Analysis) to support such an embedding of environments:

ScopeInsert.specs[26]==

$/Name/AlgInh.gnrc:inst

This macro is attached to a product file.

The facility of inserting an environment obtained from a scope property of an object is provided by the module role InhRange, which specializes RangeScope. The ModUseIdent establishes the inheritance using the module role InheritScope. The inserted outer scope is obtained from ModUseIdent.Key, the inner scope is specified by the attribute WithBody.Env. The computation of WithBody.GotInh is required to state that the inheritance is established.

ScopeInsert.lido[27]==

SYMBOL WithBody INHERITS InhRange END;

RULE: Statement ::= 'with' WithClause 'do' WithBody COMPUTE
  WithClause.InnerScope = WithBody.Env;
  WithBody.GotInh = WithClause.InheritOk;
END;

SYMBOL WithClause INHERITS InheritScope, ChkInherit END;

RULE: WithClause ::= ModUseIdent COMPUTE
  WithClause.ScopeKey = ModUseIdent.Key;
END;

This macro is attached to a product file.