File modules/editor/codemirror/mode/ruby/index.html

Last commit: Sun Dec 17 01:14:09 2017 +0100	Jan Dankert	Integration eines weiteren Code-Editors: Codemirror. Demnächst müssen wir hier mal aufräumen und andere Editoren rauswerfen.


     1 <!doctype html>
     2 
     3 <title>CodeMirror: Ruby mode</title>
     4 <meta charset="utf-8"/>
     5 <link rel=stylesheet href="../../doc/docs.css">
     6 
     7 <link rel="stylesheet" href="../../lib/codemirror.css">
     8 <script src="../../lib/codemirror.js"></script>
     9 <script src="../../addon/edit/matchbrackets.js"></script>
    10 <script src="ruby.js"></script>
    11 <style>
    12       .CodeMirror {border-top: 1px solid black; border-bottom: 1px solid black;}
    13       .cm-s-default span.cm-arrow { color: red; }
    14     </style>
    15 <div id=nav>
    16   <a href="http://codemirror.net"><h1>CodeMirror</h1><img id=logo src="../../doc/logo.png"></a>
    17 
    18   <ul>
    19     <li><a href="../../index.html">Home</a>
    20     <li><a href="../../doc/manual.html">Manual</a>
    21     <li><a href="https://github.com/codemirror/codemirror">Code</a>
    22   </ul>
    23   <ul>
    24     <li><a href="../index.html">Language modes</a>
    25     <li><a class=active href="#">Ruby</a>
    26   </ul>
    27 </div>
    28 
    29 <article>
    30 <h2>Ruby mode</h2>
    31 <form><textarea id="code" name="code">
    32 # Code from http://sandbox.mc.edu/~bennet/ruby/code/poly_rb.html
    33 #
    34 # This program evaluates polynomials.  It first asks for the coefficients
    35 # of a polynomial, which must be entered on one line, highest-order first.
    36 # It then requests values of x and will compute the value of the poly for
    37 # each x.  It will repeatly ask for x values, unless you the user enters
    38 # a blank line.  It that case, it will ask for another polynomial.  If the
    39 # user types quit for either input, the program immediately exits.
    40 #
    41 
    42 #
    43 # Function to evaluate a polynomial at x.  The polynomial is given
    44 # as a list of coefficients, from the greatest to the least.
    45 def polyval(x, coef)
    46     sum = 0
    47     coef = coef.clone           # Don't want to destroy the original
    48     while true
    49         sum += coef.shift       # Add and remove the next coef
    50         break if coef.empty?    # If no more, done entirely.
    51         sum *= x                # This happens the right number of times.
    52     end
    53     return sum
    54 end
    55 
    56 #
    57 # Function to read a line containing a list of integers and return
    58 # them as an array of integers.  If the string conversion fails, it
    59 # throws TypeError.  If the input line is the word 'quit', then it
    60 # converts it to an end-of-file exception
    61 def readints(prompt)
    62     # Read a line
    63     print prompt
    64     line = readline.chomp
    65     raise EOFError.new if line == 'quit' # You can also use a real EOF.
    66             
    67     # Go through each item on the line, converting each one and adding it
    68     # to retval.
    69     retval = [ ]
    70     for str in line.split(/\s+/)
    71         if str =~ /^\-?\d+$/
    72             retval.push(str.to_i)
    73         else
    74             raise TypeError.new
    75         end
    76     end
    77 
    78     return retval
    79 end
    80 
    81 #
    82 # Take a coeff and an exponent and return the string representation, ignoring
    83 # the sign of the coefficient.
    84 def term_to_str(coef, exp)
    85     ret = ""
    86 
    87     # Show coeff, unless it's 1 or at the right
    88     coef = coef.abs
    89     ret = coef.to_s     unless coef == 1 && exp > 0
    90     ret += "x" if exp > 0                               # x if exponent not 0
    91     ret += "^" + exp.to_s if exp > 1                    # ^exponent, if > 1.
    92 
    93     return ret
    94 end
    95 
    96 #
    97 # Create a string of the polynomial in sort-of-readable form.
    98 def polystr(p)
    99     # Get the exponent of first coefficient, plus 1.
   100     exp = p.length
   101 
   102     # Assign exponents to each term, making pairs of coeff and exponent,
   103     # Then get rid of the zero terms.
   104     p = (p.map { |c| exp -= 1; [ c, exp ] }).select { |p| p[0] != 0 }
   105 
   106     # If there's nothing left, it's a zero
   107     return "0" if p.empty?
   108 
   109     # *** Now p is a non-empty list of [ coef, exponent ] pairs. ***
   110 
   111     # Convert the first term, preceded by a "-" if it's negative.
   112     result = (if p[0][0] < 0 then "-" else "" end) + term_to_str(*p[0])
   113 
   114     # Convert the rest of the terms, in each case adding the appropriate
   115     # + or - separating them.  
   116     for term in p[1...p.length]
   117         # Add the separator then the rep. of the term.
   118         result += (if term[0] < 0 then " - " else " + " end) + 
   119                 term_to_str(*term)
   120     end
   121 
   122     return result
   123 end
   124         
   125 #
   126 # Run until some kind of endfile.
   127 begin
   128     # Repeat until an exception or quit gets us out.
   129     while true
   130         # Read a poly until it works.  An EOF will except out of the
   131         # program.
   132         print "\n"
   133         begin
   134             poly = readints("Enter a polynomial coefficients: ")
   135         rescue TypeError
   136             print "Try again.\n"
   137             retry
   138         end
   139         break if poly.empty?
   140 
   141         # Read and evaluate x values until the user types a blank line.
   142         # Again, an EOF will except out of the pgm.
   143         while true
   144             # Request an integer.
   145             print "Enter x value or blank line: "
   146             x = readline.chomp
   147             break if x == ''
   148             raise EOFError.new if x == 'quit'
   149 
   150             # If it looks bad, let's try again.
   151             if x !~ /^\-?\d+$/
   152                 print "That doesn't look like an integer.  Please try again.\n"
   153                 next
   154             end
   155 
   156             # Convert to an integer and print the result.
   157             x = x.to_i
   158             print "p(x) = ", polystr(poly), "\n"
   159             print "p(", x, ") = ", polyval(x, poly), "\n"
   160         end
   161     end
   162 rescue EOFError
   163     print "\n=== EOF ===\n"
   164 rescue Interrupt, SignalException
   165     print "\n=== Interrupted ===\n"
   166 else
   167     print "--- Bye ---\n"
   168 end
   169 </textarea></form>
   170     <script>
   171       var editor = CodeMirror.fromTextArea(document.getElementById("code"), {
   172         mode: "text/x-ruby",
   173         matchBrackets: true,
   174         indentUnit: 4
   175       });
   176     </script>
   177 
   178     <p><strong>MIME types defined:</strong> <code>text/x-ruby</code>.</p>
   179 
   180     <p>Development of the CodeMirror Ruby mode was kindly sponsored
   181     by <a href="http://ubalo.com/">Ubalo</a>.</p>
   182 
   183   </article>



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History
Sun, 17 Dec 2017 01:14:09 +0100	Jan Dankert	Integration eines weiteren Code-Editors: Codemirror. Demnächst müssen wir hier mal aufräumen und andere Editoren rauswerfen.