Scripting in AL - attempt #2.

Business Central extension adding a code editor for running scripts.

Now with code highlighting and IntelliSense!

IntelliSense is implemented naively - the main unresolved issues are:

• no autocomplete if the code preceding the current position is broken
• field name suggestions do not work in record methods like SetRange
  • for now you can use the Record.SetRange(Record.FieldName, ...) syntax
• no suggestions for function arguments

Currently? Not much. Code is parsed, semantically analyzed and executed. Message with the memory state is displayed at the end of each procedure execution.

1. Support copy-and-pasting existing AL code and running it without any changes
2. Add new features to make life easier

!TODO describe current implementation limitations

The entry point is a parameterless trigger called OnRun. You can define additional procedures with var parameters and (named) return values. Global variables are not supported (yet?).

procedure WriteLineMultiplied(text: text; count: integer)
begin
    WriteLine(text * count);
end;

trigger OnRun()
var
    hello: boolean;
    text: text;
begin
    text := 'h'   'e'   'l' * 2   'o';
    hello := 'hello' = text;

    if hello then
        text  = ' '   'world!';

    WriteLine(text);

    WriteLineMultiplied(text   ' ', 3);
end;

• ✅ - supported
• ⭕️ - planned/partially supported
• ❓ - not supported/not planned
• ❌ - not possible

• assignment (:=, =, -=, *=, /=)
• while loop
• for loop (both to and downto)
• repeat-until loop
• if and if-else statement
• exit statement - both variants, with and without an expression

!TODO list unsupported statements - case, foreach, break, ?

• unary operators
  • numeric ( , -)
  • boolean (not)
• binary operators
  • comparison (<, <=, <>, >=, >, =)
  • numeric ( , -, *, /, mod, div)
  • boolean (and, or, xor)
  • text ( , *)
    • !TODO explain * operator
  • date ( , -)
  • time ( , -)
  • datetime ( , -)

• Message(Text: Text, [Substitution: Any, ...]) (up to 10 substitutions)
• Error(Text: Text, [Substitution: Any, ...]) (up to 10 substitutions)
• WriteLine(Text: Text, [Substitution: Any, ...]) (up to 10 substitutions)
• Abs(Number: Decimal): Decimal
• Power(Number: Decimal, Power: Decimal): Decimal
• Format(Input: Any, [Length: Integer, [FormatNumber: Integer]]): Text
• Format(Input: Any, [Length: Integer, [FormatString: Text]]): Text
• CalcDate(Formula: Text, [Date: Date]): Date
• CalcDate(Formula: DateFormula, [Date: Date]): Date
• ClosingDate(Date: Date): Date
• CreateDateTime(Date: Date, Time: Time): DateTime
• CurrentDateTime(): DateTime
• NormalDate(Date: Date): Date
• Time(): Time
• Today(): Date
• WorkDate([WorkDate: Date]): Date
• Date2DMY(Date: Date, Part: Integer): Integer
• Date2DWY(Date: Date, Part: Integer): Integer
• DMY2Date(Day: Integer, [Month: Integer, [Year: Integer]]): Date
• DWY2Date(WeekDay: Integer, [Week: Integer, [Year: Integer]]): Date
• DT2Date(DateTime: DateTime): Date
• DT2Time(DateTime: DateTime): Time
• CreateGuid(): Guid
• IsNullGuid(Guid: Guid): Boolean
• Evaluate(var Value: Any, Input: Text, [FormatNumber: Integer])[: Boolean]

!TODO list unsupported and planned

1. editor improvements
   • better intellisense
   • ui - hide editor before symbols are received
2. remaining record methods
3. blobs streams file management
4. case, continue
5. more built-in functions and methods
6. option, enum, others
7. allow Record.SetRange(Record.Field, ...);
8. strlen as a method?

React app addin using the Monaco Editor for script input.