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#
# Copyright (c) 2009-2010, Stephen B. Weston
#
# This is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as published
# by the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
# USA
izip <- function(...) {
iterators <- lapply(list(...), iter)
if (length(iterators) == 0) {
nextEl <- function() {
stop('StopIteration', call.=FALSE)
}
} else {
nextEl <- function() {
lapply(iterators, nextElem)
}
}
object <- list(nextElem=nextEl)
class(object) <- c('abstractiter', 'iter')
object
}
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