Programming Language Concepts Review Guide

Understand the different programming paradigms:

• imperative/procedural
• object-oriented
• functional
• logical/declarative (only the basic idea and the example language Prolog)

Understand the difference between syntax and semantics.

Understand the difference between static and dynamic properties of programs.

Understand the difference between static and dynamic allocation

• fully static (e.g., Fortran)
• fully dynamic (e.g., LISP)
• mixed/stack-based (e.g., C)

Know some history of programming languages:

• Fortran
• Cobol
• LISP
• C
• Java

Be ready to discuss language design criteria

• efficiency (of operation, implementation, programming, maintenance)
• writability
• readability
• regularity: generality, orthogonality, uniformity
• expressiveness, extensibility, restrictability, machine-independence, security, etc.

Understand the lexical structure of languages

• tokens & token categories (reserved words, identifiers, etc.)
• context-free grammars
• BNF & EBNF notation
• parse trees and abstract syntax trees
• ambiguous grammars
• expressing operator associativity and precedence in grammars

Understand basic semantics

• attributes of variables (type, location, value, scope, lifetime)
• different binding times for attributes of variables
• static vs. dynamic bindings
• scope of binding
• symbol table
• static vs. dynamic scope
• stack/automatic allocation, and activation records
• heap/dynamic (manual) allocation
• R-value and L-value
• variable aliases
• dangling references & garbage

Control flow

• Short-circuiting
• Expression (returns a value) vs. Statement (results in assignment)
• "Side effects" in procedural vs. functional languages
• Iteration vs. recursion

Data Types

• Denotational (name) vs. structural definitions
• Purpose of a type system
• What does "strong typing" mean? Example language?
• Static typing -- example language?
• Scalar vs. composite types
• Casting vs. coercion
• Shallow vs. deep variable comparisons

Subroutines

• Formal vs. Actual parameters
• Function vs. procedure
• General layout of stack -- static & dynamic links
• Content of stack frame
• Calling sequence specifications
• Passing by value, passing by reference, passing by value/result

Programming:

• Be ready to write a simple function in Scheme

• Be ready to write either a functional or procedural rountine in C or Java (simple)

• Be ready to interpret/debug example functional and procedural programs

• Be ready to write a simple Perl program, or interpret/debug an example

• Understand the Perl data types and how to use them.

• Understand regular expressions and be ready to create or debug regular expressions

• Understand the difference between G2 variables and local names

• Be ready to debug simple G2 rules or procedures

• Be able to differentiate event-driven and data-driven processing in G2

• Be ready to compare and contrast Scheme, Perl, and G2 with respect to
• variables and scope
• regularity
• language paradigm
• applications
• advantages and disadvantages

For the Final Exam, you may bring 1 sheet of paper with notes, to which you may refer during the exam.