Synthesis

The book “Limbaje de programare și compilatoare” (Editura Academiei RSR, 1987) is conceived as a unified synthesis between the theoretical foundations and the engineering techniques required for the definition and implementation of programming languages. It emerged from an advanced long-duration course (three semesters), taught from 1980 onward by bringing together automata theory, formal languages, and compilers. Its stake is both “human” and technical: language is the principal convention of human-computer cooperation, while the compiler is the mechanism that makes this convention executable, transforming programs from descriptions into real processes — not through disparate recipes, but through a coherent methodology.

The central idea of the book is that program translation can be treated as a formalizable operation: a systematic transformation between two descriptions of the same algorithm, from the source language toward forms closer to the machine. In this framework, each language implicitly corresponds to a virtual machine that gives meaning to its constructs, and compilation becomes the interface discipline between the universe of this virtual machine and that of the real machine.

The structure is explicitly tripartite, preceded by a conceptual introduction on systems, information, communication, languages, and translation, precisely in order to establish that a compiler is not a trick, but an answer to a general need for the controlled transformation of representations:

• Part I – Programming Languages constructs the anatomy of the object to be translated. Languages are analyzed as lexical-syntactic-semantic layered systems, through the lens of implementation: variables (including the address/value duality), attributes and binding, declarations, data structures, expressions and statements, procedures and parameter passing, runtime memory management (static allocation, stack, heap).
• Part II – Introduction to Compiler Theory presents the formalism strictly necessary for compiler design: the Chomsky hierarchy, regular and context-free languages, finite automata and pushdown automata, syntax-directed translation schemes, translation automata, and attribute grammars (Knuth) as the bridge between syntax and semantics.
• Part III – Compiler Design is the workshop in which the compiler becomes a factory: lexical analysis, syntactic analysis (the LL and LR families), semantic analysis, intermediate code (trees, three-address code, backpatching), the symbol table, errors, optimizations, object-code generation, interpreters, assemblers and macro-assembly, up to relocatable modules and the role of the linker.

The book is distinguished by its refusal to separate theory from practice: each topic follows the path motivation – algorithm – implementation, forming not only technical knowledge, but also a discipline of thought. A unifying element is the systematic recourse to the model of the machine (abstract / virtual, with states, stack, tables, and actions), which structures the same logic from recognition to translation and then to code generation, offering the reader a way of thinking extensible to the design of other complex software applications.