Language Definition

 

This section defines NESL. It is not meant as a formal semantics but, along with the full definition of the syntax in Appendix A and description of all the built-in functions in Appendix B, it should serve as an adequate description of the language. NESL is a strict first-order strongly-typed language with the following data types:

• four primitive atomic data types: booleans (bool), integers (int), characters (char), and floats (float);

• the primitive sequence type;

• the primitive pair type;

• and user definable compound datatypes;

and the following operations:

• a set of predefined functions on the primitive types;

• three primitive constructs: a conditional construct if, a binding construct let, and the apply-to-each construct;

• and a function constructor, function, for defining new functions.

This section covers each of these topics.

• Data
  • Atomic Data Types
  • Sequences ([])
  • Record Types (datatype)
• Functions and Constructs
  • Conditionals (if)
  • Binding Local Variables (let)
  • The Apply-to-Each Construct ({})
  • Defining New Functions (function)
  • Top-Level Bindings (=)