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Version 2 (modified by hopscc, 17 years ago)

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Cobra Differences From C#

See also  Cobra Forums Differences with C#

  • Dynamic Typing and Type inference (doesnt require Type or keyword to declare locals)
    • optional type declarations
  • Block structured by indentation only (like Python) no squiggly braces (brackets)
  • nil tracking - variables can be declared as nil assignable (or not)
  • Built in language support for
    • unit test code
    • assertions
    • Design by contract - invariants, preconditions and postconditions
  • Syntax support for builtin
    • Lists - [] - List of Dynamic
    • Dictionaries - {:} Dictionary of <Dynamic, Dynamic>
    • Sets - {}
  • Line Oriented
    • # to comment line (instead of //)
    • No multiline comments
    • _ to continue line
    • Tab or Spaces to indent line ( Fixed 4 space indent), Cannot mix Tabs and spaces for an indent level
  • Methodnames and properties start with lowercase. (i.e lowerCamelCase)
    • Access to methods/properties in used libraries are also done via (implicitly mapped ) lowerCamelCase methodnames
  • Class names must be CamelCased?
  • instance variable optionally prefixed with _ (implicitly makes them private). If so prefixed can be accessed directly in methods
  • methods (and properties) invoked with leading this. or more usually just ..
  • constructor method called init, has no return value

  • String type accessed as string rather than String
  • ditto int and uint and float and double types ( rather than Int, UInt, Float, Double)
  • int and uint types all the same naming
    • int8, int16, int/int32, int64 instead of SByte, Int16, Int32/int, Int64
    • uint8, uint16, uint/uint32, uint64 instead of Byte, UInt16,...
  • Variable specification - typing, access modifiers, argument attributes by keyword 'as' rather than C-like syntax
    • e.g. x as int32, instVar as string public
  • typecasting by keyword to as in 'x to Type' rather than '(Type)x'
    • cast to and away from nilable Type.
  • as shared to declare a static type
  • <> instead of != for 'not equals' comparisons
  • nil for no object (null) value
  • Supports +=, -=, etc. It does not support ++ or -- unary operators ( use += 1 and -= 1 instead).

  • boolean conditions can be tested on any type. True is any of
    • numeric not 0
    • not nil
    • non empty List or Dictionary
  • Strings delimited by single or double quotes, normal range of \c expansion ( e.g \n, \t)
  • Substitute expressions (values) directly in strings by enclosing with [].
    • such expressions can have optional String.format specification
  • 'Raw' Strings (r"a raw string") no escape sequence expansion
  • 'NoSubstitution' strings ( ns" no substitution [done] here")
  • DocStrings on Programs, classes, Instane variables, methods and properties
  • Different syntax for characters c'x'
  • ref keyword for getting pointer to method ( reference) rather calling it ( for delegates)
  • sig keyword or declaring a delegate type
  • def keyword to declare a method/function
    • e.g def doCalc( start as int) as int instead of int doCalc( int start)
  • use keyword instead of 'using' to get access to a non default namespace
  • branch... on, on, [else] statement rather than c# case statement
  • Slicing syntax for sequences (Lists and Strings) [start:stop:step] as well as normal library subsequence methods (substring, range, ...)
  • numeric for loop uses slice syntax. e.g. for i in 1:10:1 vs for( int i =1; i<=10; i++)
  • more to come