# Command: cvt_a

NEST HelpDesk | Command Index | NEST Quick Reference

Name:

    cvt_a - Converts an array to the equivalent type trie.

      Synopsis:  /name array cvt_a -> trie

Examples:

      /pop [/anytype [-pop-]]  cvt_a -> trie

Description:

      cvt_a tries to construct a type-trie object from a given array.
      The supplied literal is used as name for the trie-object.

      WARNING:
      Be very careful when using this function. If the supplied
      array is not well formed, the interpreter will abort
      ungracefully!

      Tries should not be constructed fron scratch using cvt_a.
      Use the operators trie and addtotrie for this purpose.
      Rather, cvt_a is provided to correct minor errors in tries
      with the help of cva_t.

Parameters:

      The supplied array is the root trie node.
      The layout of each trie node must conform to the following
      pattern:
      [/type [next] [alt]] for non-leaf nodes and
      [object]	 for leaf nodes.

      /type is  a literal, representing the expected type.
      object is any type of token. It is returned when this leaf of
      the trie is reached.
      [next] is an array, representig the next parameter levels.
      [alt] is an array, representig parameter alternatives
      at the current level.

      This pattern recursively defines a type-trie. Note, however,
      that violations of this definition are handled ungracefully.

Bugs:

      Errors should be handled gracefully.

Diagnostics:

      This operation is low level and does not raise
      errors. If the array is ill-formed, the interpreter will
      abort!

Remarks:

      cvt_a is the inverse function to cva_t.
      If cvt_a is applied to the result of cva_t, it yields
      the original argument:
      /name [array] cvt_a cva_t -> /name [array]

Author:

      Marc-Oliver Gewaltig

FirstVersion:

      May 20 1999

SeeAlso:

- cva_t
- trie
- addtotrie
- type
- cst
- cva
- cv1d
- cv2d
- cvd
- cvi
- cvlit
- cvn
- cvs

Source:

    /opt/conda/conda-bld/nest_1510213973486/work/nest-2.14.0/sli/slitypecheck.cc

NEST HelpDesk | Command Index | NEST Quick Reference

© 2004 The NEST Initiative