NAME

cru_cbop - conditional binary operator for the cru library

SYNOPSIS

#include <cru/cru.h>

typedef struct cru_cbop_s
{
   cru_bpred bpred;
   cru_bop bop;
} *cru_cbop;

DESCRIPTION

A conditional binary operator represents a binary operator whose result is required only if some predicate is true of its operands. When conditional operators are passed to cru library functions, they are used only as follows:

• First the predicate is applied to the operands.
• If the predicate returns any non-zero value, then a result is obtained from the operator applied to those same operands.
• If the predicate returns zero, the operator is not invoked and therefore not required to produce any valid result.

A NULL bpred field causes the operator to be invoked unconditionally.

ERRORS

The bop field has no default value and must be initialized to something other than NULL. Otherwise, an error of CRU_UNDCBO is reported for an undefined conditional binary operator.

NOTES

Conditional binary operators appear in the postponement field of a cru_postponer and in the e_prod field of a cru_crosser. In both cases the operands are a pair of edge labels and the result returned by the operator is the label of a newly created or modified edge.

FILES

/usr/local/include/cru/function_types.h

/usr/local/include/cru/data_types.h

SEE ALSO

cru, cru_bop, cru_bpred, cru_builder, cru_built, cru_classifier, cru_class_of, cru_class_size, cru_composed, cru_composer, cru_connect, cru_connector, cru_cqop, cru_crossed, cru_crosser, cru_ctop, cru_ctop_pair, cru_ctop_quad, cru_data_types, cru_deduplicated, cru_destructor, cru_destructor_pair, cru_edge_count, cru_fabricated, cru_fabricator, cru_filter, cru_filtered, cru_fold, cru_free_kill_switch, cru_free_later, cru_free_now, cru_free_partition, cru_function_types, cru_get, cru_hash, cru_induced, cru_inducer, cru_kernel, cru_kill, cru_killed, cru_mapreduced, cru_mapreducer, cru_merged, cru_merger, cru_mutated, cru_mutator, cru_new_kill_switch, cru_nop, cru_order, cru_order_pair, cru_partition_of, cru_plan, cru_postponed, cru_postponer, cru_prop, cru_prop_pair, cru_pruner, cru_qop, cru_qpred, cru_set, cru_sig, cru_singleton, cru_split, cru_splitter, cru_spread, cru_strerror, cru_stretch, cru_stretched, cru_stretcher, cru_subconnector, cru_terminus_count, cru_top, cru_tpred, cru_united, cru_uop, cru_vertex_count, cru_zone

AUTHOR

Dennis Furey (milonga@delayinsensitive.com)

PROJECT PAGE

https://github.com/gueststar/cru