ToC DocOverview CGDoc RelNotes Index PermutedIndex
Allegro CL
Home Previous Up Next Table of Contents Index
  ANSI Common Lisp   22 Printer   22.1 The Lisp Printer   22.1.3 Default Print-Object Methods

22.1.3.8 Printing Other Arrays

If *print-array* is true and *print-readably* is false, any array other than a vector is printed using #nA format. Let n be the rank of the array. Then # is printed, then n as a decimal integer, then A, then n open parentheses. Next the elements are scanned in row-major order, using write on each element, and separating elements from each other with whitespace1. The array's dimensions are numbered 0 to n-1 from left to right, and are enumerated with the rightmost index changing fastest. Every time the index for dimension j is incremented, the following actions are taken:

  • If j < n-1, then a close parenthesis is printed.

  • If incrementing the index for dimension j caused it to equal dimension j, that index is reset to zero and the index for dimension j-1 is incremented (thereby performing these three steps recursively), unless j=0, in which case the entire algorithm is terminated. If incrementing the index for dimension j did not cause it to equal dimension j, then a space is printed.

  • If j < n-1, then an open parenthesis is printed.

This causes the contents to be printed in a format suitable for :initial-contents to make-array. The lists effectively printed by this procedure are subject to truncation by *print-level* and *print-length*.

If the array is of a specialized type, containing bits or characters, then the innermost lists generated by the algorithm given above can instead be printed using bit-vector or string syntax, provided that these innermost lists would not be subject to truncation by *print-length*.

If both *print-array* and *print-readably* are false, then the array is printed in a format (using #<) that is concise but not readable.

If *print-readably* is true, the array prints in an implementation-defined manner; see the variable *print-readably*. In particular, this may be important for arrays having some dimension 0.

For information on how the Lisp reader parses these "other arrays," see Section 2.4.8.12 Sharpsign A.


Home Previous Up Next Table of Contents Index
© Franz Inc. 1998-2019 - File last updated 02-07-2019