Documentation

Description

The Pseudocode console allows executing pseudocode and defining correct output for checking answers.

You can select code from Programming Command Prompt or by calling executeCode from JS.

Properties

The list starts with the common properties, learn more about them by visiting the Modules description section. The other available properties are described below.

Language syntax

The language is similar to Pascal. All variable definitions are extracted to a separated variable block and a user can't define any new variable in a code.

• variable block block which contains all variable definitions for a function. Variables should be separated by a comma. Variable block is always optional. If variable block exists, then this block must be in a separate line.

  variable <variable_name1>, <variable_name2>=<variable_start_value>, ..., <variable_nameN>
  

  Examples:

  function testFunction ()
  variable a,b
  begin
  

  
  

  program testProgram
  variable a,b = 2
  begin
  

• array block block which contains all arrays' definitions extracted to a separated block. A user cannot define a new array variable in the code.

  array <variable_name_1>[<size_as_number_1>], <variable_name_2>[<size_as_number_2], ..., <variable_name_n>[<size_as_number_n]
  

  or

  array <variable_name_1>[<size_as_number_1>] = [<value_1>, <value_2>]
  

  • Arrays are counted from 0.

  Examples:

  program A
  array a[2], b[3], c[20]
  begin
  
  end
  

  
  

  program A
  array a[2] = [1, 2]
  begin
  
  end
  

• get array element

  <array_variable>[<index_as_number>]
  

• Math and logic operations are available:

  >: greater
  >=: greater or equal
  <: less
  <=: less or equal
  ==: equal
  !=: different
  or: logical or
  and: logical and
  ( ): brackets for operations order
  +: addition
  -: substraction
  /: division
  /_: division without rest
  *: multiplication
  %: modulo
  

• string starts with " and ends with ". In string " can be escaped by \" characters.

  Examples:

  "This is \" still string"
  

• instruction each line can contain only one instruction call expected instructions calls as a call argument.

  <instruction_name>(<argument1 or function call>, <argument2 or function call>, ..., <argumentN or function call>)
  

  • Instruction name must match with [A-Za-z_][a-zA-Z0-9_]* regexp.

• code block block which contains code instructions.

  begin
      <code>
  end
  

  • Begin and end instructions always must be in separate lines.

  Examples:

  begin
      instructionA()
  end
  

• main function is function which will be called first.

  program <program_name>
  begin
      <code>
  end
  

  • Each program must have one and only one main function.
  • Program name definition must be in separate line.

  Examples:

  program programName
  begin
  
  end
  

  
  

  program programName
  variable a,be
  begin
  
  end
  

• function can be defined by user in pseudocode.

  function <function_name> (<argument1>, <argument2>, ..., <argumentN>)
  begin
      <code>
  
      return <data>
  end
  

  • Function header definition must be in a separate line.
  • Return statement is optional. If function doesn't contain return, then at default it will return 0. Return statement must be in a separate line.
  • Defined functions must be at the beginning of the code.
  • An instruction name must match to [A-Za-z_][a-zA-Z0-9_]* regexp.

  Examples:

  function test ()
  variable a, b
  begin
      a = someCode()
  end
  

  
  

  function test2(a, b, c)
  begin
      b = anotherFunction()
      return b
  end
  

• if statement executes code when expression will return true.

  if <expression> then
      <instruction_call or code_block>
  

  or

  if <expression> then
      <instruction_call or code_block>
  else
      <instruction_call or code_block>
  

  • "If" instruction definition header must be in a separate line.
  • "Else" instruction is optional and must be in a separate line.

  Examples:

  if a == 2 then
  begin
      a = a + 2
      myFunction(a)
  end
  

  
  

  if a == 2 then
      myFunction(a)
  else
  begin
      a = a + 1
      myFunction(a)
  end
  

  
  

  if a == 2 then
      return 2
  else
      return 1
  

• case allows improving code clarity by changing multiple "if" statements to one case statement. The program will enter to the option code if a variable value is equal to an option value.

  case <variable_name>
      option <number_or_string>, ... , <number_or_string> then
          <instruction_call or code_block>
      option <number_or_string>, ... , <number_or_string> then
          <instruction_call or code_block>
  
      ...
  
      option <number_or_string>, ... , <number_or_string> then
          <instruction_call or code_block>
  

  • "Case" instruction definition header and "option" instruction definition header must be in separate lines.
  • "Case" option value can be a string or a number.

  Examples:

  case someVariable
      option 1 then 
      begin
          print ("Block")
          print ("Is cool")
      end
      option 2,4 then 
          print("2")
      option "3" then 
          print("3 as text")
  

• for allows iterating in the range of <from_number_or_variable; to_number_or_variable>.

  for <variable_name> from <number_or_variable> to <number_or_variable> do
      <instruction_call or code_block>
  
  for <variable_name> from <number_or_variable> to <number_or_variable> by <number> do
      <instruction_call or code_block>
  
  for <variable_name> from <number_or_variable> downto <number_or_variable> do
      <instruction_call or code_block>
  
  for <variable_name> from <number_or_variable> downto <number_or_variable> by <number> do
      <instruction_call or code_block>
  

  • "For" instruction header must be in a separate line.
  • "To" can be value or variable.
  • "for" with "downto" statement will decrement counter.
  • "for" without "by" statement will increment/decrement by 1.

  Examples:

  for myVariable from 1 to 40 by 4 do
  begin
      print("myVariable\n")
  end
  

• while loop allows executing the same code while expression returns true.

  while <expression> do
      <instruction_call or code_block>
  

  • While header definition must be in a separate line.
  • Expression will be checked before executing code.

  Examples:

  while a <= 5 do
  begin
      print(a)
      a = a + 1
  end
  

• do while works similar to while instruction. Main difference is when the expression is checked.

  do
      <instruction_call or code_block>
  while (<expression>)
  

  • In do while loop, expression will be checked after executing a code so the code will be always called.

  Examples:

  do
      write("OK")
  while(1 == 2)
  

• method call

  <object_name>.<method_name>(<argument1>, <argument2>, ..., <argumentn>)
  

  Examples:

  myArray.extend(2)
  

  
  

Console

Functions defined in Functions list property contains in builtIn.console console object. This console gives the possibility of reading input from console and writing to console. Example access to console is builtIn.console.Write("text");.

Console functions:

• Write(text)
• ReadLine(callback), where callback will receive text as first argument
• ReadChar(callback), where callback will receive text as first argument

Ready console wrappers for Functions List property

• print

  builtIn.console.Write(arguments[0].value);
  

  Usage in user code: print("Text")

• read

  var receivedValue = arguments[0];
  builtIn.console.ReadLine(function (value) {
      builtIn.retVal.value = builtIn.objects.String.__constructor__(value);
  });
  

  Usage in user code: variableToRead = read()

• readChar

  var receivedValue = arguments[0];
  builtIn.console.ReadChar(function (value) {
      builtIn.retVal.value = builtIn.objects.String.__constructor__(value);
  });
  

  Usage in user code: variableToRead = readChar()

Supported commands

Events

The Pseudocode Console addon sends ValueChanged event when the score has been calculated.

CSS classes

1.1 Answer scope and "builtIn" variable in functions defined in Functions list property

Answer scope and variable "builtIn" in functions defined in Functions list property are the same. So, saving data in function like: builtIn.data.wroteValue = arguments[0] will be visible in answer (for example: this.wroteValue === 'ok').

Answer scope contains additional property calledInstructions where addon automatically will count how many times instruction was called. This object contains fields:

    for: <called_count>,
    while: <called_count>,
    doWhile: <called_count>,
    if: <called_count>,
    case: <called_count>

Each field of calledInstructions will be incremented when built-in instruction will be called in user code. For example, after executing this code:

    program test
    variable a
    begin
        a = 2
        if a == 2 then
            write("ok")
    end

then in answer code this.calledInstructions.if will equal to 1.

For loops calledInstructions will contain how many times loop executes code. For example after executing this code in answer:

    program test
    variable a
    begin
        for a from 1 to 4 do
            write(a)
    end

then in answer code this.calledInstructions.for will contain 4.

1.2 Variable object

Each variable in language is a JS object.

    {
        value: <value>
        type: "<type>"
        methods: used by language
        parent: used by language
    }

Creating new variables should be done by builtIn.objects object which contains all builtIn objects. For creating a new variable __constructor__ function must be called (for example builtIn.objects.Number.__constructor__(2))

Built in types:

• Object.__constructor__()
• Number.__constructor__(<Optionally start value, if not defined then will receive 0>)
• String.__constructor__(<Optionally start value, if not defined then will reveive "">)
• Boolean.__constructor__(<Optionally start value, if not defined then will receive false>)
• Array.__constructor__(<Required count as number;>, <Optionally start values as array of valid pseudocode console objects. At default array will be empty (null objects)>)

There is no way to convert one type to second, so while receiving value from a user, checking type should be added manually.

Warning:

To functions defined in the Functions list or methods defined in Methods list property argument is passed as reference, so while changing argument value, the original value will be changed too. In arguments[0].value = 2; new value of first argument will be visible in user code, but arguments[0] = {value: 2}; wont be visible in user code.

To functions defined by user arguments will be passed as copy.

1.3 builtIn object:

builtIn object is available in any function defined in Functions list property and in any method defined in Methods list property. The same builtIn object is provided for each function or method, so if builtIn object was changed while executing function a then while executing function b this object will contain changed values.

builtIn object fields:

• console object which contains access to user console.
• data object, which is initially empty. In this object data to be checked while checking answer should be saved. Saving data in data object must be done manualy in functions defined in Functions list property or in methods defined in Methods list property.
• retVal object which contains returned value by function defined in Functions list property or method defined in Methods list property. Saved value to return should be set in value field in builtIn.retVal object.
• objects reference to constructors of built in objects.

1.4 Return value:

Returns value from function or method that is provided as reference in builtIn.retVal object. To return value, value field in buildIn.retVal must contain correct object. For example:

    builtIn.retVal.value = builtIn.objects.String.__constructor__("'" + this.value + "'");

If function returns value, then the type of this object must be the one of the built-in types.

2.1 Answer example

For addon with activated run user code and Run parameters: 227 and 9956, defined functions in Functions list:

• write

  builtIn.console.Write(arguments[0].value);
  

• read

  builtIn.console.ReadLine(function (value) {
    if (/^\d+(.\d+)?$/.test(value)) {
      builtIn.retVal.value = builtIn.objects.Number.__constructor__(value);
    } else {
      builtIn.retVal.value = builtIn.objects.String.__constructor__(value);
    }
  });
  

• printSum (here is saving answer in scope)

  var answer = arguments[0];
  builtIn.data.answer = answer.value;
  
  builtIn.console.Write(answer.value + '');
  

and defined exercise as: "Write the sum of two numbers with the 'printSum' function".

For checking the correct answer, the valid code would be:

    if (this.data.answer == 10183) {
      return true;
    }

    return false;

In this code we can check how many times built-in function was called with this.calledInstructions object.

Demo presentation

Demo presentation contains examples showing how this addon can be used.