Info Catalog octave: Keywords octave: Grammar and Parser

octave: Parser

 
 F.2 Parser
 ==========
 
 The parser has a number of variables that affect its internal operation.
 These variables are generally documented in the manual alongside the
 code that they affect.  For example, ‘allow_noninteger_range_as_index’
 is discussed in the section on index expressions.
 
    In addition, there are three non-specific parser customization
 functions.  ‘add_input_event_hook’ can be used to schedule a user
 function for periodic evaluation.  ‘remove_input_event_hook’ will stop a
 user function from being evaluated periodically.
 
  -- : ID = add_input_event_hook (FCN)
  -- : ID = add_input_event_hook (FCN, DATA)
      Add the named function or function handle FCN to the list of
      functions to call periodically when Octave is waiting for input.
 
      The function should have the form
 
           FCN (DATA)
 
      If DATA is omitted, Octave calls the function without any
      arguments.
 
      The returned identifier may be used to remove the function handle
      from the list of input hook functions.
 
      See also: remove_input_event_hook
      XREFremove_input_event_hook.
 
  -- : remove_input_event_hook (NAME)
  -- : remove_input_event_hook (FCN_ID)
      Remove the named function or function handle with the given
      identifier from the list of functions to call periodically when
      Octave is waiting for input.
 
      See also: add_input_event_hook XREFadd_input_event_hook.
 
    Finally, when the parser cannot identify an input token it calls a
 particular function to handle this.  By default, this is the internal
 function "__unimplemented__" which makes suggestions about possible
 Octave substitutes for MATLAB functions.
 
  -- : VAL = missing_function_hook ()
  -- : OLD_VAL = missing_function_hook (NEW_VAL)
  -- : missing_function_hook (NEW_VAL, "local")
      Query or set the internal variable that specifies the function to
      call when an unknown identifier is requested.
 
      When called from inside a function with the "local" option, the
      variable is changed locally for the function and any subroutines it
      calls.  The original variable value is restored when exiting the
      function.
 
      See also: missing_component_hook XREFmissing_component_hook.
 

Info Catalog octave: Keywords octave: Grammar and Parser