lib/console.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #     http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 # Defines some ANSI Terminal Control Escape Sequences.
  16 module console
  17
  18 # A ANSI/VT100 escape sequence.
  19 abstract class TermEscape
  20         # The US-ASCII ESC character.
  21         protected fun esc: Char do return 27.ascii
  22 end
  23
  24 # ANSI/VT100 code to switch character attributes (SGR).
  25 #
  26 # By default, resets everything to the terminal’s defaults.
  27 #
  28 # Note:
  29 #
  30 # The escape sequence inserted at the end of the string by terminal-related
  31 # methods of `String` resets all character attributes to the terminal’s
  32 # defaults. So, when combining format `a` and `b`, something like
  33 # `("foo".a + " bar").b` will not work as expected, but `"foo".a.b + " bar".b`
  34 # will. You may also use `TermCharFormat` (this class).
  35 #
  36 # Usage example:
  37 #
  38 #     print "{(new TermCharFormat).yellow_fg.bold}a{(new TermCharFormat).yellow_fg}b{new TermCharFormat}"
  39 class TermCharFormat
  40         super TermEscape
  41
  42         private var attributes: Array[String] = new Array[String]
  43
  44         # Copies the attributes from the specified format.
  45         init from(format: TermCharFormat) do
  46                 attributes.add_all(format.attributes)
  47         end
  48
  49         redef fun to_s: String do return "{esc}[{attributes.join(";")}m"
  50
  51         # Apply the specified SGR and return `self`.
  52         private fun apply(sgr: String): TermCharFormat do
  53                 attributes.add(sgr)
  54                 return self
  55         end
  56
  57         # Apply normal (default) format and return `self`.
  58         fun default: TermCharFormat do return apply("0")
  59
  60         # Apply bold weight and return `self`.
  61         fun bold: TermCharFormat do return apply("1")
  62
  63         # Apply underlining and return `self`.
  64         fun underline: TermCharFormat do return apply("4")
  65
  66         # Apply blinking or bold weight and return `self`.
  67         fun blink: TermCharFormat do return apply("5")
  68
  69         # Apply reverse video and return `self`.
  70         fun inverse: TermCharFormat do return apply("7")
  71
  72         # Apply normal weight and return `self`.
  73         fun normalWeight: TermCharFormat do return apply("22")
  74
  75         # Add the attribute that disable inderlining and return `self`.
  76         fun not_underlined: TermCharFormat do return apply("24")
  77
  78         # Add the attribute that disable blinking and return `self`.
  79         fun steady: TermCharFormat do return apply("25")
  80
  81         # Add the attribute that disable reverse video and return `self`.
  82         fun positive: TermCharFormat do return apply("27")
  83
  84         # Apply a black foreground and return `self`.
  85         fun black_fg: TermCharFormat do return apply("30")
  86
  87         # Apply a red foreground and return `self`.
  88         fun red_fg: TermCharFormat do return apply("31")
  89
  90         # Apply a green foreground and return `self`.
  91         fun green_fg: TermCharFormat do return apply("32")
  92
  93         # Apply a yellow foreground and return `self`.
  94         fun yellow_fg: TermCharFormat do return apply("33")
  95
  96         # Apply a blue foreground and return `self`.
  97         fun blue_fg: TermCharFormat do return apply("34")
  98
  99         # Apply a mangenta foreground and return `self`.
 100         fun magenta_fg: TermCharFormat do return apply("35")
 101
 102         # Apply a cyan foreground and return `self`.
 103         fun cyan_fg: TermCharFormat do return apply("36")
 104
 105         # Apply a white foreground and return `self`.
 106         fun white_fg: TermCharFormat do return apply("37")
 107
 108         # Apply the default foreground and return `self`.
 109         fun default_fg: TermCharFormat do return apply("39")
 110
 111         # Apply a black backgroud and return `self`.
 112         fun black_bg: TermCharFormat do return apply("40")
 113
 114         # Apply a red backgroud and return `self`.
 115         fun red_bg: TermCharFormat do return apply("41")
 116
 117         # Apply a green backgroud and return `self`.
 118         fun green_bg: TermCharFormat do return apply("42")
 119
 120         # Apply a yellow backgroud and return `self`.
 121         fun yellow_bg: TermCharFormat do return apply("43")
 122
 123         # Apply a blue backgroud and return `self`.
 124         fun blue_bg: TermCharFormat do return apply("44")
 125
 126         # Apply a mangenta backgroud and return `self`.
 127         fun magenta_bg: TermCharFormat do return apply("45")
 128
 129         # Apply a cyan backgroud and return `self`.
 130         fun cyan_bg: TermCharFormat do return apply("46")
 131
 132         # Apply a white backgroud and return `self`.
 133         fun white_bg: TermCharFormat do return apply("47")
 134
 135         # Apply the default backgroud and return `self`.
 136         fun default_bg: TermCharFormat do return apply("49")
 137 end
 138
 139 # Redefine the `String` class to add functions to color the string.
 140 redef class String
 141         private fun apply_format(f: TermCharFormat): String do
 142                 return "{f}{self}{normal}"
 143         end
 144
 145         private fun normal: TermCharFormat do return new TermCharFormat
 146
 147         # Make the text appear in dark gray (or black) in a ANSI/VT100 terminal.
 148         #
 149         # WARNING: SEE: `TermCharFormat`
 150         fun gray: String do return apply_format(normal.black_fg)
 151
 152         # Make the text appear in red in a ANSI/VT100 terminal.
 153         #
 154         # WARNING: SEE: `TermCharFormat`
 155         fun red: String do return apply_format(normal.red_fg)
 156
 157         # Make the text appear in green in a ANSI/VT100 terminal.
 158         #
 159         # WARNING: SEE: `TermCharFormat`
 160         fun green: String do return apply_format(normal.green_fg)
 161
 162         # Make the text appear in yellow in a ANSI/VT100 terminal.
 163         #
 164         # WARNING: SEE: `TermCharFormat`
 165         fun yellow: String do return apply_format(normal.yellow_fg)
 166
 167         # Make the text appear in blue in a ANSI/VT100 terminal.
 168         #
 169         # WARNING: SEE: `TermCharFormat`
 170         fun blue: String do return apply_format(normal.blue_fg)
 171
 172         # Make the text appear in mangenta in a ANSI/VT100 terminal.
 173         #
 174         # WARNING: SEE: `TermCharFormat`
 175         fun purple: String do return apply_format(normal.magenta_fg)
 176
 177         # Make the text appear in cyan in a ANSI/VT100 terminal.
 178         #
 179         # WARNING: SEE: `TermCharFormat`
 180         fun cyan: String do return apply_format(normal.cyan_fg)
 181
 182         # Make the text appear in light gray (or white) in a ANSI/VT100 terminal.
 183         #
 184         # WARNING: SEE: `TermCharFormat`
 185         fun light_gray: String do return apply_format(normal.white_fg)
 186
 187         # Make the text appear in bold in a ANSI/VT100 terminal.
 188         #
 189         # WARNING: SEE: `TermCharFormat`
 190         fun bold: String do return apply_format(normal.bold)
 191
 192         # Make the text underlined in a ANSI/VT100 terminal.
 193         #
 194         # WARNING: SEE: `TermCharFormat`
 195         fun underline: String do return apply_format(normal.underline)
 196 end