is_lazystream: is functions

In TobCap/lazystreamr: Provides basic functions that handle lazy stream objects

Description

Check if an object is lcons class.

Usage

is.lpair(x)

is.lpair_not_llist(x)

is.llist(x)

is.llist_atomic_maybe(x, depth = 10)

Arguments

x	a lcons object
depth	for is.llist_atomic_maybe's

Details

lcons() attach "lcons" class for output. is.lpair() simply checks this attribute. is.llist(x) returns TRUE if x is lempty or ltail(x) is llist, or ltail(x) and ltail(ltail(x)) is the same expression in cdr part (promise part, i.e., function body) for infinit-stream. is.lpair_not_list(x) retuns TRUE if x is lcons but not llist. is.llist_atomic_maybe(x) checks if lhead(x) is R's atomic object for several loops. If the checking arrives its limit loop, this returns structure(TRUE, class = "maybe"). The default limit is ten.

Examples

is.lpair(lempty) # => FALSE
is.lpair_not_llist(lempty) # => FALSE
is.llist(lempty) # => TRUE

is.lpair(1 %:% 2) # => TRUE
is.lpair_not_llist(1 %:% 2) # => TRUE
is.llist(1 %:% 2) # => FALSE

is.lpair(1 %..% 2) # => TRUE
is.lpair_not_llist(1 %..% 2) # => FALSE
is.llist(1 %..% 2) # => TRUE

ones <- 1 %:% ones
is.llist(ones) # => TRUE # circular reference
is.llist(1 %..% Inf) #=> TRUE #

is.llist_atomic_maybe(1 %..% 10) # => TRUE
is.llist_atomic_maybe(1 %..% 11) # => structure(TRUE, class = "maybe")
is.llist_atomic_maybe(1 %..% Inf) # => structure(TRUE, class = "maybe")

TobCap/lazystreamr documentation built on May 9, 2019, 4:50 p.m.