Module: Trxl::HelpFunction0

Defined in:

lib/trxl/trxl_grammar.rb

Instance Method Summary

• #eval(env = Environment.new) ⇒ Object
• #to_s(env = Environment.new) ⇒ Object

Instance Method Details

#eval(env = Environment.new) ⇒ Object

# File 'lib/trxl/trxl_grammar.rb', line 4729

def eval(env = Environment.new)
  to_s(env)
end

#to_s(env = Environment.new) ⇒ Object

# File 'lib/trxl/trxl_grammar.rb', line 4733

def to_s(env = Environment.new)
  help =  "-----------------------------------------\n"
  help =  "           TRXL Language HELP            \n"
  help =  "-----------------------------------------\n"
  help << "1)  Built in operators:\n"
  help << "    +,-,*,/,%,==,!=,<=,>=,<,>,;\n"
  help << "-----------------------------------------\n"
  help << "2)  Integers and floats in arithmetics:\n"
  help << "    1 or 2.33333 or 0.34 or .34\n"
  help << "-----------------------------------------\n"
  help << "3)  Arbitrary nesting of parentheses:\n"
  help << "    (1+2*(5+((3+4)*3)-6/2)+7*2)\n"
  help << "    => 61\n"
  help << "-----------------------------------------\n"
  help << "4)  Comments:\n"
  help << "    # A comment until the end of the line\n"
  help << "    /* A longer comment that\n"
  help << "       spans multiple lines\n"
  help << "     */\n"
  help << "-----------------------------------------\n"
  help << "5)  Built in keywords:\n"
  help << "    TRUE,FALSE,NULL,IF,ELSE,END\n"
  help << "-----------------------------------------\n"
  help << "6)  Built in functions:\n"
  help << "    HELP,ENV,SIZE,SPLIT,ROUND,MIN,MAX\n"
  help << "    SUM,MULT,AVG, PRINT, PRINT_LINE\n"
  help << "    TO_INT, TO_FLOAT, TO_ARRAY\n"
  help << "-----------------------------------------\n"
  help << "7)  Standard library functions:\n"
  help << "    Use to iterate over Arrays or Strings\n"
  help << "    FOREACH_IN, INJECT\n"
  help << "-----------------------------------------\n"
  help << "8)  Access the current environment:\n"
  help << "    ENV; (your output may differ)\n"
  help << "    => { :a => 3, :foo => 5 }\n"
  help << "    Given the following environment:\n"
  help << "    { :a => 1, :b => 2, :c => 3 }\n"
  help << "    ENV['a']\n"
  help << "    => 1\n"
  help << "    ENV['a'..'b']\n"
  help << "    => { :a => 1, :b => 2 }\n"
  help << "-----------------------------------------\n"
  help << "9)  Numeric variables and literals\n"
  help << "    3;\n"
  help << "    => 3\n"
  help << "    a = 3;\n"
  help << "    => 3\n"
  help << "    a;\n"
  help << "    => 3\n"
  help << "-----------------------------------------\n"
  help << "10) String variables and literals\n"
  help << "    \"This is a string\";\n"
  help << "    => \"This is a string\";\n"
  help << "    'This is a string';\n"
  help << "    => \"This is a string\";\n"
  help << "    s1 = \"This is a string\"; s1;\n"
  help << "    => \"This is a string\"\n"
  help << "    s2 = 'This is a string'; s2;\n"
  help << "    => \"This is a string\"\n"
  help << "    SIZE(s1);\n"
  help << "    => 16\n"
  help << "    SIZE(\"foo\");\n"
  help << "    => 3\n"
  help << "-----------------------------------------\n"
  help << "11) Variables and closure applications\n"
  help << "    a = 3; foo = 5;\n"
  help << "    calc = fun(x,y) { (x + y) * a + foo };\n"
  help << "    calc(2,2);\n"
  help << "    => 17\n"
  help << "-----------------------------------------\n"
  help << "12) Array variables and literals\n"
  help << "    arr = [1, [fun(){2}()], fun(x){x}(3)]\n"
  help << "    SIZE(arr);\n"
  help << "    => 3\n"
  help << "    SIZE([1,2,3]);\n"
  help << "    => 3\n"
  help << "    [1,2,3] + [4,[5,6]];\n"
  help << "    => [1,2,3,4,[5,6]]\n"
  help << "    [1,2,3] - [[1],2,3];\n"
  help << "    => [1]\n"
  help << "-----------------------------------------\n"
  help << "13) Hash variables and literals\n"
  help << "    h = { 1 => fun(){2}(), 'a' => 'foo' }\n"
  help << "    SIZE(h);\n"
  help << "    => 2\n"
  help << "    h[1];\n"
  help << "    => 'fun(){2}()'\n"
  help << "    h['a'];\n"
  help << "    => 'foo'\n"
  help << "    SIZE({ 1 => 2});\n"
  help << "    => 1\n"
  help << "-----------------------------------------\n"
  help << "14) Range variables and literals\n"
  help << "    range_including_upper = 1..5\n" 
  help << "    => [ 1, 2, 3, 4, 5 ]\n" 
  help << "    SIZE(range_including_upper);\n"
  help << "    => 5\n"
  help << "    range_excluding_upper = 1...5\n"
  help << "    => [ 1, 2, 3, 4 ]\n" 
  help << "    SIZE(range_excluding_upper);\n"
  help << "    => 4\n"
  help << "    SIZE([1..5);\n"
  help << "    => 5\n"
  help << "-----------------------------------------\n"
  help << "15) Conditional branching and recursion:\n"
  help << "    factorial = fun(x) {\n"
  help << "      if(x == 0)\n" 
  help << "        1\n" 
  help << "      else\n"
  help << "        x * factorial(x - 1)\n"
  help << "      end\n"
  help << "    }\n"
  help << "    factorial(5);\n"
  help << "    => 120\n"
  help << "-----------------------------------------\n"
  help << "16) Conditional branching:\n"
  help << "    foo = fun(x) {\n"
  help << "      if(x == 0)\n" 
  help << "        0\n" 
  help << "      elsif(x == 1)\n"
  help << "        1\n"
  help << "      else\n"
  help << "        2\n"
  help << "      end\n"
  help << "    }\n"
  help << "    foo(0);\n"
  help << "    => 0\n"
  help << "    foo(1);\n"
  help << "    => 1\n"
  help << "    foo(2);\n"
  help << "    => 2\n"
  help << "-----------------------------------------\n"
  help << "17) case expressions:\n"
  help << "    foo = fun(x) {\n"
  help << "      case x\n" 
  help << "        when 0 then 0\n" 
  help << "        when 1 then 1\n" 
  help << "        when 2 then 2\n" 
  help << "        else 3\n"
  help << "      end\n"
  help << "    }\n"
  help << "    foo(1);\n"
  help << "    => 1\n"
  help << "    foo(3);\n"
  help << "    => 3\n"
  help << "-----------------------------------------\n"
  help
end