str_view html widget

Author: hadley

DESCRIPTION

@@ -18,5 +18,7 @@ Imports:
     magrittr
 Suggests:
     testthat,
-    knitr
+    knitr,
+    htmltools,
+    htmlwidgets
 VignetteBuilder: knitr

NAMESPACE

@@ -36,6 +36,7 @@ export(str_to_lower)
 export(str_to_title)
 export(str_to_upper)
 export(str_trim)
+export(str_view)
 export(str_wrap)
 export(word)
 import(stringi)

NEWS.md

@@ -1,5 +1,8 @@
 # stringr 1.0.0.9000
 
+* `str_view()` creates an HTML widget to display regular expression 
+  matches (#96).
+
 * The replacement to `perl()` is `regex()` not `regexp()` (#61).
 
 # stringr 1.0.0

R/view.R

@@ -0,0 +1,26 @@
+#' View HTML rendering of regular expression match.
+#'
+#' @inheritParams str_detect
+#' @export
+#' @examples
+#' str_view(c("abc", "def", "fgh"), "[aeiou]")
+#' str_view(c("abc", "def", "fgh"), "^")
+str_view <- function(x, pattern) {
+  loc <- str_locate(x, pattern)
+
+  # How to do escaping? Need to update x and loc
+
+  has_match <- !is.na(loc[, "start"])
+  str_sub(x[has_match], loc[has_match, , drop = FALSE]) <-
+    paste0("<span class='match'>", str_sub(x[has_match], loc[has_match, , drop = FALSE]), "</span>")
+
+  bullets <- htmltools::HTML(str_c(
+    "<ul>\n",
+    str_c("  <li>", x, "</li>", collapse = "\n"),
+    "\n</ul>"
+  ))
+
+  htmlwidgets::createWidget("str_view", list(html = bullets),
+    sizingPolicy = htmlwidgets::sizingPolicy(knitr.figure = FALSE, defaultHeight = NA),
+    package = "stringr")
+}

inst/htmlwidgets/lib/str_view.css

@@ -0,0 +1,11 @@
+.str_view ul, .str_view li {
+  list-style: none;
+  padding: 0;
+  margin: 0.5em 0;
+  font-family: monospace;
+}
+
+.str_view .match {
+  border: 1px solid #ccc;
+  background-color: #eee;
+}

inst/htmlwidgets/str_view.js

@@ -0,0 +1,17 @@
+HTMLWidgets.widget({
+
+  name: 'str_view',
+
+  type: 'output',
+
+  initialize: function(el, width, height) {
+  },
+
+  renderValue: function(el, x, instance) {
+    el.innerHTML = x.html;
+  },
+
+  resize: function(el, width, height, instance) {
+  }
+
+});

inst/htmlwidgets/str_view.yaml

@@ -0,0 +1,5 @@
+dependencies:
+ - name: str_view
+   version: 0.1.0
+   src: htmlwidgets/lib/
+   stylesheet: str_view.css

man/str_view.Rd

@@ -0,0 +1,32 @@
+% Generated by roxygen2 (4.1.1): do not edit by hand
+% Please edit documentation in R/view.R
+\name{str_view}
+\alias{str_view}
+\title{View HTML rendering of regular expression match.}
+\usage{
+str_view(x, pattern)
+}
+\arguments{
+\item{pattern}{Pattern to look for.
+
+  The default interpretation is a regular expression, as described
+  in \link[stringi]{stringi-search-regex}. Control options with
+  \code{\link{regex}()}.
+
+  Match a fixed string (i.e. by comparing only bytes), using
+  \code{\link{fixed}(x)}. This is fast, but approximate. Generally,
+  for matching human text, you'll want \code{\link{coll}(x)} which
+  respects character matching rules for the specified locale.
+
+  Match character, word, line and sentence boundaries with
+  \code{\link{boundary}()}. An empty pattern, "", is equivalent to
+  \code{boundary("character")}.}
+}
+\description{
+View HTML rendering of regular expression match.
+}
+\examples{
+str_view(c("abc", "def", "fgh"), "[aeiou]")
+str_view(c("abc", "def", "fgh"), "^")
+}
+