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diff --git a/project/templates/thue2a.html b/project/templates/thue2a.html index 04da9eb..7cc9a5b 100644 --- a/project/templates/thue2a.html +++ b/project/templates/thue2a.html @@ -15,11 +15,11 @@ <h5>1/1/2017</h5> -<p><a href="http://esolangs.org/wiki/Thue" target="_blank">Thue</a> is an esoteric programming -language based on unrestricted grammars. A Thue program consists of a number of rules detailing -a sequence of symbols to replace and a sequence of symbols to replace with, and an initial -state of the program. Applicable rules are then applied to the inital state in a random -order until no more are applicable, at which point the program terminates.</p> +<p><a href="http://esolangs.org/wiki/Thue" class="external">Thue</a> is an esoteric programming +language based on unrestricted grammars. A Thue program consists of a number of rules detailing a +sequence of symbols to replace and a sequence of symbols to replace with, and an initial state of +the program. Applicable rules are then applied to the inital state in a random order until no more +are applicable, at which point the program terminates.</p> <p>An example Thue program that increments a binary number surrounded by '_' characters:</p> <div class="precontain"> @@ -35,11 +35,11 @@ _1111111_ </code> </div> -<p>The before and after symbols in each rule are separated by '::=' and the list of rules is -ended by a blank rule. Note that whitespace in rules and the inital state is NOT ignored.</p> +<p>The before and after symbols in each rule are separated by '::=' and the list of rules is ended +by a blank rule. Note that whitespace in rules and the inital state is NOT ignored.</p> -<p>Output is handled by prefixing the right hand side with '~', which causes those symbols to -go to stdout and the replacement in the program to be the empty string.</p> +<p>Output is handled by prefixing the right hand side with '~', which causes those symbols to go to +stdout and the replacement in the program to be the empty string.</p> <p>The traditional Hello World program:</p> <div class="precontain"> @@ -50,9 +50,9 @@ a </code> </div> -<p>Input is handled by having the right hand side of a rule be ':::', which causes the left -hand side symbols to be replaced with a line from the standard output. Unfortunately, this -immediately causes problems.</p> +<p>Input is handled by having the right hand side of a rule be ':::', which causes the left hand +side symbols to be replaced with a line from the standard output. Unfortunately, this immediately +causes problems.</p> <p>The following is an innocent piece of code that accepts a single line of input and does nothing more. Maybe.</p> @@ -65,13 +65,13 @@ a </div> <p>If a string involving the letter 'a' is entered into the above program, the single input rule -will again become applicable and another line of input will be obtained. In other words, the -input in Thue is unescaped and allows direct code injection into a program.</p> +will again become applicable and another line of input will be obtained. In other words, the input +in Thue is unescaped and allows direct code injection into a program.</p> <p>To solve this problem, I've constructed a slightly modified version of Thue that I'm calling version 2a. In this version, all symbols obtained through stdin are treated as different from -ordinary symbols. Rules can refer to and manipulate symbols obtained through stdin by -surrounding them in double quotes.</p> +ordinary symbols. Rules can refer to and manipulate symbols obtained through stdin by surrounding +them in double quotes.</p> <p>A rule that replaces an ordinary symbol 'a' with 'abc':</p> <div class="precontain"> @@ -99,8 +99,8 @@ a::=abc </pre> </div> -<p>While this doesn't solve all the problems Thue has (try writing a Thue program that asks -for and greets the user by name!) it should solve this one particular issue.</p> +<p>While this doesn't solve all the problems Thue has (try writing a Thue program that asks for and +greets the user by name!) it should solve this one particular issue.</p> {% endblock %} |