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% File src/library/base/man/try.Rd
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% File src/library/base/man/try.Rd
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% Part of the R package, https://www.R-project.org
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% Part of the R package, https://www.R-project.org
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% Copyright 1995-2016 R Core Team
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% Copyright 1995-2021 R Core Team
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% Distributed under GPL 2 or later
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% Distributed under GPL 2 or later
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\name{try}
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\name{try}
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\alias{try}
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\alias{try}
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\title{Try an Expression Allowing Error Recovery}
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\title{Try an Expression Allowing Error Recovery}
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  instead of the default \code{\link{stderr}()},
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  instead of the default \code{\link{stderr}()},
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  notably when \code{try()} is used inside a \code{\link{Sweave}} code
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  notably when \code{try()} is used inside a \code{\link{Sweave}} code
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  chunk and the error message should appear in the resulting document.
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  chunk and the error message should appear in the resulting document.
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}
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}
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\value{
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\value{
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  The value of the expression if \code{expr} is evaluated without error,
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  The value of the expression if \code{expr} is evaluated without error:
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  but an invisible object of class \code{"try-error"} containing the
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  otherwise an invisible object inheriting from class \code{"try-error"}
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  error message, and the error condition as the \code{"condition"}
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  containing the error message with the error condition as the
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  \code{"condition"} attribute.
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}
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\section{Warning}{
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  attribute, if it fails.
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  Do not test\preformatted{
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    if (class(res) == "try-error"))
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}
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  as if there is no error, the result might (now or in future) have a
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  class of length > 1. Use \code{if(\link{inherits}(res, "try-error"))}
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  instead.
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}
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}
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\seealso{
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\seealso{
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  \code{\link{options}} for setting error handlers and suppressing the
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  \code{\link{options}} for setting error handlers and suppressing the
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  printing of error messages;
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  printing of error messages;
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  \code{\link{geterrmessage}} for retrieving the last error message.
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  \code{\link{geterrmessage}} for retrieving the last error message.