REXX - Features


REXX has the following characteristics and features:

  • simple syntax
  • small instruction set containing just two dozen instructions
  • freeform syntax
  • case insensitive tokens, including variable names
  • character string basis
  • dynamic data typing, no declarations
  • no reserved keywords, except in local context
  • arbitrary numerical precision
  • decimal arithmetic, floating-point
  • a rich selection of built-in functions, especially string and word processing
  • automatic storage management
  • crash protection
  • content addressable data structures
  • associative arrays
  • straightforward access to system commands and facilities
  • simple error-handling, and built-in tracing and debugger
  • few artificial limitations
  • simplified I/O facilities
  • unconventional operators
  • only partly supports Unix style command line parameters, except specific implementations
  • provides no basic terminal control as part of the language, except specific implementations
  • provides no generic way to include functions and subroutines from external libraries, except specific implementations

REXX has just twenty-three, largely self-evident, instructions (e.g., call, parse, and select) with minimal punctuation and formatting requirements. It is essentially an almost free-form language with only one data-type, the character string; this philosophy means that all data are visible (symbolic) and debugging and tracing are simplified.

REXX syntax looks similar to PL/I, but has fewer notations; this makes it harder to parse (by program) but easier to use, except for cases where PL/I habits may lead to surprises.

Read more about this topic:  REXX

Famous quotes containing the word features:

    The features of our face are hardly more than gestures which force of habit made permanent. Nature, like the destruction of Pompeii, like the metamorphosis of a nymph into a tree, has arrested us in an accustomed movement.
    Marcel Proust (1871–1922)

    Each reader discovers for himself that, with respect to the simpler features of nature, succeeding poets have done little else than copy his similes.
    Henry David Thoreau (1817–1862)

    Art is the child of Nature; yes,
    Her darling child, in whom we trace
    The features of the mother’s face,
    Her aspect and her attitude.
    Henry Wadsworth Longfellow (1807–1882)