Add help tab to regex_gadget

DESCRIPTION

     purrr,
     dplyr,
     rmarkdown,
+    knitr,
     utils,
     tidyr,
     rstudioapi,

NAMESPACE

 importFrom(dplyr,filter)
 importFrom(dplyr,group_by)
 importFrom(dplyr,mutate)
+importFrom(dplyr,select)
 importFrom(dplyr,summarize)
 importFrom(utils,getFromNamespace)

R/regex_gadget.R

 
   ui <- miniPage(
     shiny::includeCSS(system.file("style.css", package = "regexplain")),
+    shiny::includeCSS(system.file("gadget.css", package = "regexplain")),
     gadgetTitleBar(
       "regexplain",
       right = miniTitleBarButton("done", "Send Regex To Console", TRUE)
       miniTabPanel(
         "Help", icon = icon("support"),
         miniContentPanel(
-          tags$p("Help will go here.")
+          fillRow(
+            flex = c(1, 4),
+            tagList(
+              # selectInput("help_category", "Category", c("", unique(cheatsheet$category))),
+              # uiOutput("help_group"),
+              tags$ul(
+                id = "help-sidebar",
+                tags$li("Character Classes", class = "header"),
+                tags$ul(
+                  class = "subgroup",
+                  tags$li(actionLink("help_cat_character_classes_regular", "Regular")),
+                  tags$li(actionLink("help_cat_character_classes_prebuilt", "Pre-Built"))
+                ),
+                tags$li(actionLink("help_cat_anchors", "Anchors")),
+                tags$li("Escaped Characters", class = "header"),
+                tags$ul(
+                  class = "subgroup",
+                  tags$li(actionLink("help_cat_escaped_general", "General")),
+                  tags$li(actionLink("help_cat_escaped_hex", "Hex")),
+                  tags$li(actionLink("help_cat_escaped_control", "Control Characters"))
+                ),
+                tags$li(actionLink("help_cat_groups", "Groups")),
+                tags$li(actionLink("help_cat_quantifiers", "Quantifiers"))
+              )
+            ),
+            tags$div(
+              style = "width: 100%; padding-left: 10px;",
+              uiOutput('help_text_selected')
+            )
+          )
         )
       )
     )
       print(x)
     })
 
+    # output$help_group <- renderUI({
+    #   req(input$help_category)
+    #   groups <- unique(cheatsheet[cheatsheet$category == input$help_category, ]$group)
+    #   if (is.na(groups[1])) {
+    #     NULL
+    #   } else {
+    #     selectInput("help_group", "Group", groups)
+    #   }
+    # })
+
+    # ---- Help Section ---- #
+    help_text <- reactiveVal("<p>Select a category from the left sidebar.</p>")
+
+    output$help_text_selected <- renderUI({
+      HTML(help_text())
+    })
+
+    make_html_table <- function(x) {
+      select(x, .data$regexp, .data$text) %>%
+        knitr::kable(
+          col.names = c("Regexp", "Text"),
+          escape = FALSE,
+          format = "html")
+    }
+
+    observeEvent(input$help_cat_character_classes_regular, {
+      cheatsheet %>%
+        filter(category == "character classes", group == "regular") %>%
+        make_html_table %>%
+        help_text
+    })
+
+    observeEvent(input$help_cat_character_classes_prebuilt, {
+      cheatsheet %>%
+        filter(category == "character classes", group == "pre-built") %>%
+        make_html_table %>%
+        help_text
+    })
+
+    observeEvent(input$help_cat_anchors, {
+      cheatsheet %>%
+        filter(category == "anchors") %>%
+        make_html_table %>%
+        help_text
+    })
+
+    observeEvent(input$help_cat_escaped_general, {
+      cheatsheet %>%
+        filter(category == "escaped characters", group == "general") %>%
+        make_html_table %>%
+        help_text
+    })
+
+    observeEvent(input$help_cat_escaped_hex, {
+      cheatsheet %>%
+        filter(category == "escaped characters", group == "hex") %>%
+        make_html_table %>%
+        help_text
+    })
+
+    observeEvent(input$help_cat_escaped_control, {
+      cheatsheet %>%
+        filter(category == "escaped characters", group == "control characters") %>%
+        make_html_table %>%
+        help_text
+    })
+
+    observeEvent(input$help_cat_groups, {
+      cheatsheet %>%
+        filter(category == "groups") %>%
+        make_html_table %>%
+        help_text
+    })
+
+    observeEvent(input$help_cat_quantifiers, {
+      cheatsheet %>%
+        filter(category == "quantifiers") %>%
+        make_html_table %>%
+        help_text
+    })
+
+
     observeEvent(input$done, {
       # browser()
       if (input$pattern != "") {

R/utils.R

-#' @importFrom dplyr "%>%" mutate filter group_by summarize
+#' @importFrom dplyr "%>%" mutate filter group_by summarize select
 #' @importFrom utils getFromNamespace
 NULL
 

data-raw/cheatsheet.R

+cheatsheet <- tibble::tribble(
+  ~category, ~group, ~regexp, ~text,
+  "character classes", "regular", "<code>.</code>", "any character except newline",
+  "character classes", "regular", "<code>\\w</code> <code>\\d</code> <code>\\s</code>", "word, digit, whitespace",
+  "character classes", "regular", "<code>\\W</code> <code>\\D</code> <code>\\S</code>", "not word, digit, whitespace",
+  "character classes", "regular", "<code>\\p{property name}</code>", "matches character with unicode property, like <code>\\p{Uppercase}</code>, see <a href=\"http://www.unicode.org/reports/tr44/#Property_Index.\">unicode property list</a>.",
+  "character classes", "regular", "<code>[abc]</code>", "any of a, b or c",
+  "character classes", "regular", "<code>[^abc]</code>", "not a, b, or c",
+  "character classes", "regular", "<code>[a-g]</code> <code>[1-3]</code>", "character between a & g or 1 & 3",
+  "character classes", "regular", "<code>[\\^\\-]</code>", "matches <code>-</code> or <code>\\</code>",
+  "character classes", "pre-built", "Used inside <code>[]</code>", "Example <code>[[:digit:]AX]</code> matches all digits and A and X",
+  "character classes", "pre-built", "<code>[:punct:]</code>", "punctuation",
+  "character classes", "pre-built", "<code>[:alpha:]</code>", "letters",
+  "character classes", "pre-built", "<code>[:lower:]</code>", "lowercase letters",
+  "character classes", "pre-built", "<code>[:upper:]</code>", "uppercase letters",
+  "character classes", "pre-built", "<code>[:digit:]</code>", "digits",
+  "character classes", "pre-built", "<code>[:xdigit:]</code>", "hex digits",
+  "character classes", "pre-built", "<code>[:alnum:]</code>", "letters and numbers",
+  "character classes", "pre-built", "<code>[:cntrl:]</code>", "control characters",
+  "character classes", "pre-built", "<code>[:graph:]</code>", "letters, numbers, and punctuation",
+  "character classes", "pre-built", "<code>[:print:]</code>", "letters, numbers, punctuation, and whitespace",
+  "character classes", "pre-built", "<code>[:space:]</code>", "space characters (basically equivalent to <code>\\s</code>)",
+  "character classes", "pre-built", "<code>[:blank:]</code>", "space and tab",
+  "anchors", NA, "<code>^</code>", "start of string",
+  "anchors", NA, "<code>$</code>", "end of string",
+  "anchors", NA, "<code>\\b</code>", "word boundary",
+  "anchors", NA, "<code>\\B</code>", "not-word boundary",
+  "anchors", NA, "<code>\\A</code>", "stringr multiline: match start of the input",
+  "anchors", NA, "<code>\\z</code>", "stringr multiline: match end of the input",
+  "anchors", NA, "<code>\\Z</code>", "stringr multiline: match end of the input, but before final line terminator (if it exists)",
+  "escaped characters", "general", "<code>\\.</code>", "dot",
+  "escaped characters", "general", "<code>\\*</code>", "asterisk",
+  "escaped characters", "general", "<code>\\\\</code>", "backslash",
+  "escaped characters", "general", "<code>\\t</code>", "tab",
+  "escaped characters", "general", "<code>\\n</code>", "linefeed",
+  "escaped characters", "general", "<code>\\r</code>", "carriage return",
+  "escaped characters", "hex", "<code>\\xhh</code>", "2 hex digits",
+  "escaped characters", "hex", "<code>\\x{hhhh}</code>", "1-6 hex digits",
+  "escaped characters", "hex", "<code>\\uhhhh</code>", "4 hex digitis",
+  "escaped characters", "hex", "<code>\\Uhhhhhhhh</code>", "8 hex digits",
+  "escaped characters", "hex", "<code>\\N{name}</code>", "Name of unicode character, e.g. <code>\\N{grinning face}</code>",
+  "escaped characters", "control characters", "<code>\\a</code>", "bell",
+  "escaped characters", "control characters", "<code>\\cX</code>", "match a control-X character",
+  "escaped characters", "control characters", "<code>\\e</code>", "escape (<code>\\u001B</code>)",
+  "escaped characters", "control characters", "<code>\\f</code>", "form feed (<code>\\u000C</code>)",
+  "escaped characters", "control characters", "<code>\\0ooo</code>", "octal character where \"ooo\" is 1-3 octal digits",
+  "groups", NA, "<code>(abc)</code>", "capture group",
+  "groups", NA, "<code>\\<N></code>", "backreference to group #N, e.g. <code>\\1</code>",
+  "groups", NA, "<code>(?:abc)</code>", "non-capturing group, e.g. <code>\"gr(?:e|a)y\")</code>",
+  "groups", NA, "<code>(?=abc)</code>", "postive lookahead; matches are followed by <code>abc</code> (non-capturing)",
+  "groups", NA, "<code>(?!abc)</code>", "negative lookahead; matches are not followed by <code>abc</code> (non-capturing)",
+  "groups", NA, "<code>(?<=abc)</code>", "positive lookbehind; matches are preceeded by <code>abc</code> (non-capturing)",
+  "groups", NA, "<code>(?<!abc)</code>", "negative lookbehind; matches are not preceeded by <code>abc</code> (non-capturing)",
+  "groups", NA, "<code>(?>abc)</code>", "atomic-match; no back-tracking if later matches fail",
+  "quantifiers", NA, "<code>a*</code>", "0 or more",
+  "quantifiers", NA, "<code>a+</code>", "1 or more",
+  "quantifiers", NA, "<code>a?</code>", "0 or 1",
+  "quantifiers", NA, "<code>a{n}</code>", "exactly n times",
+  "quantifiers", NA, "<code>a{n,}</code>", "n or more times",
+  "quantifiers", NA, "<code>a{n,m}</code>", "n-m times",
+  "quantifiers", NA, "add <code>+</code>", "makes match possessive",
+  "quantifiers", NA, "add <code>?</code>", "makes match non-greedy",
+  "quantifiers", NA, "<code>ab|cd</code>", "match ab or cd",
+  "quantifiers", NA, "<code>w(?:o|a)ke</code>", "use non-capturing group for precedence"
+)
+

inst/gadget.css

+th,
+td {
+  padding: 10px 13px;
+  text-align: left;
+  border-bottom: 1px solid #E1E1E1; }
+th:first-child,
+td:first-child {
+  padding-left: 0; }
+th:last-child,
+td:last-child {
+padding-right: 0; }
+
+#help-sidebar {
+  padding-top: 5px;
+  padding-left: 10px;
+}
+#help-sidebar ul {
+  list-style-type: none;
+  font-size: 1.1em;
+}
+#help-sidebar li {
+  list-style: none;
+}
+#help-sidebar .header li {
+  padding: 3px;
+}
+#help-sidebar a {
+  display: block;
+  width: 100%;
+  text-decoration: none;
+  text-align: left;
+  padding: 3px;
+}
+#help-sidebar .subgroup {
+  padding-left: 0px;
+}
+#help-sidebar .subgroup a {
+  padding-left: 15px;
+}
+#help-sidebar a:hover {
+  background-color: #eee;
+  text-decoration: none;
+}