Scripting builtins

[ThibautHH]

Scripting builtins

Implement if, while and foreach control structures and the special expression syntax.

Control structures

• if (<expr>) then ... [else ... ]endif
• while (<expr>) ... end
• foreach <var> (<words>) ... end

Expressions

• Mathematical operators (+, -, *, /, %)
• + and - are right-associative
• Comparison operators (==, !=, <, <=, >, >=)
• == and != compare strings; the rest, numbers
• Pattern matching operators (=~, !~)
• Regex engine?
• Logical operators (&&, ||, !)
• Bit-wise and bitshift operators (~, &, |, ^, <<, >>)
• Precedence override (())
  Null or missing operands are considered to be 0.

File inquiries (-<letter> <file>)

• r, w, x: Read, write and execute permissions respectively
• o: Have ownership
• e: Is (Existence)
• z: Is empty (zero size file)
• f: Is regular file
• d: Is directory