NAME ^

src/pmc/iterator.pmc - Iterator PMC

DESCRIPTION ^

These are the vtable functions for the Iterator base class. Iterators are used in combination with other classes(mainly aggregates) to visit all entries in that aggregate.

SYNOPSIS ^

default usage ^

    .local pmc iterator, array, entry
    iterator = new 'Iterator', array
  iter_loop:
    unless iterator, iter_end  # while (more values)
    entry = shift iterator     # get an entry
    ...
    goto iter_loop
  iter_end:

The new can alteratively be written as:

  iterator = iter array

iterate from the end, for arrays ^

    .local pmc iterator, array, entry
    iterator = new 'Iterator', array
    iterator = .ITERATE_FROM_END
  iter_loop:
    unless iterator, iter_end  # while (more values)
    entry = pop iterator     # get an entry
    ...
    goto iter_loop
  iter_end:

iterate over a hash ^

    .local pmc iterator, hash, key, entry
    iterator = new 'Iterator', hash
  iter_loop:
    unless iterator, iter_end  # while (more values)
    key   = shift iterator     # get the key..
    entry = hash[key]
    ...
    goto iter_loop
  iter_end:

Methods ^

void init()
Raises an exception. Use init_pmc().
void init_pmc(PMC *initializer)
Initializes the iterator with an aggregate PMC. Defaults iteration mode to iterate from start.
void mark()
Marks the current idx/key and the aggregate as live.
PMC *clone()
Make a clone of the iterator.
INTVAL get_integer()
Get number of remaining elements. Does not work for hashes yet. TODO: keep track of current position and direction
STRING *get_string()
Returns a textual representation of the iterator.
INTVAL get_integer_keyed(PMC *key)
INTVAL get_integer_keyed_int(INTVAL idx)
Get integer value of current position plus idx.
FLOATVAL get_number_keyed(PMC *key)
FLOATVAL get_number_keyed_int(INTVAL idx)
Get number value of current position plus idx.
STRING *get_string_keyed(PMC *key)
STRING *get_string_keyed_int(INTVAL idx)
Get string value of current position plus idx.
INTVAL get_bool()
Returns true if the idx/key is not -1.
INTVAL elements()
Returns the number of remaining elements in the aggregate. TODO.
PMC *get_pmc_keyed(PMC *key)
Returns the element for *key.
PMC *get_pmc_keyed_int(INTVAL key)
Returns the element for key.
void set_integer_native(INTVAL value)
Reset the Iterator. value must be one of 
 ITERATE_FROM_START        ... Iterate from start
 ITERATE_FROM_START_KEYS   ... OrderedHash by keys
 ITERATE_FROM_END          ... Arrays only
INTVAL pop_integer()
FLOATVAL pop_float()
STRING *pop_string()
PMC *pop_pmc()
Returns the element for the current idx/key and sets the idx/key to the previous one.
INTVAL shift_integer()
Returns the element for the current idx/key and sets the idx/key to the next one.
opcode_t *invoke(void *next)
Return the next element of the aggregate. The return type may depend on the aggregate. If there are no more items in the aggregate, I1 .. I4 are zero.See docs/pdds/pdd03_calling_conventions.pod.
FLOATVAL shift_float()
STRING *shift_string()
PMC *shift_pmc()
Returns the element for the current idx/key and sets the idx/key to the next one.
INTVAL exists_keyed(PMC *key)
Returns whether an element for *key exists in the aggregate.
INTVAL exists_keyed_int(INTVAL idx)
Returns whether an element for idx exists in the aggregate.
INTVAL defined()
Returns whether the iterator contains an aggregate.
INTVAL defined_keyed(PMC *key)
INTVAL defined_keyed_int(INTVAL key)
Returns the result of calling defined_keyed(key) on the aggregate.


 parrot