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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/view.R
\name{str_view}
\alias{str_view}
\alias{str_view_all}
\title{View strings and matches}
\usage{
str_view(
string,
pattern = NULL,
match = TRUE,
html = FALSE,
use_escapes = FALSE
)
}
\arguments{
\item{string}{Input vector. Either a character vector, or something
coercible to one.}
\item{pattern}{Pattern to look for.
The default interpretation is a regular expression, as described in
\code{vignette("regular-expressions")}. Use \code{\link[=regex]{regex()}} for finer control of the
matching behaviour.
Match a fixed string (i.e. by comparing only bytes), using
\code{\link[=fixed]{fixed()}}. This is fast, but approximate. Generally,
for matching human text, you'll want \code{\link[=coll]{coll()}} which
respects character matching rules for the specified locale.
Match character, word, line and sentence boundaries with
\code{\link[=boundary]{boundary()}}. An empty pattern, "", is equivalent to
\code{boundary("character")}.}
\item{match}{If \code{pattern} is supplied, which elements should be shown?
\itemize{
\item \code{TRUE}, the default, shows only elements that match the pattern.
\item \code{NA} shows all elements.
\item \code{FALSE} shows only elements that don't match the pattern.
}
If \code{pattern} is not supplied, all elements are always shown.}
\item{html}{Use HTML output? If \code{TRUE} will create an HTML widget; if \code{FALSE}
will style using ANSI escapes.}
\item{use_escapes}{If \code{TRUE}, all non-ASCII characters will be rendered
with unicode escapes. This is useful to see exactly what underlying
values are stored in the string.}
}
\description{
\code{str_view()} is used to print the underlying representation of a string and
to see how a \code{pattern} matches.
Matches are surrounded by \verb{<>} and unusual whitespace (i.e. all whitespace
apart from \code{" "} and \code{"\\n"}) are surrounded by \code{{}} and escaped. Where
possible, matches and unusual whitespace are coloured blue and \code{NA}s red.
}
\examples{
# Show special characters
str_view(c("\"\\\\", "\\\\\\\\\\\\", "fgh", NA, "NA"))
# A non-breaking space looks like a regular space:
nbsp <- "Hi\u00A0you"
nbsp
# But it doesn't behave like one:
str_detect(nbsp, " ")
# So str_view() brings it to your attention with a blue background
str_view(nbsp)
# You can also use escapes to see all non-ASCII characters
str_view(nbsp, use_escapes = TRUE)
# Supply a pattern to see where it matches
str_view(c("abc", "def", "fghi"), "[aeiou]")
str_view(c("abc", "def", "fghi"), "^")
str_view(c("abc", "def", "fghi"), "..")
# By default, only matching strings will be shown
str_view(c("abc", "def", "fghi"), "e")
# but you can show all:
str_view(c("abc", "def", "fghi"), "e", match = NA)
# or just those that don't match:
str_view(c("abc", "def", "fghi"), "e", match = FALSE)
}
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