BlitzMax/Language/Expressions

Operators BlitzMax supports the following operators. Operators are grouped into levels of precedence, starting with the highest precedence operators: Operator Syntax Sub expression ( Expression ) New object New Typename Literal Value Identifier Value Self object Self Super object Super Null value Null Pi Pi True True False False Minimum Min ( Expression1 , Expression2 ) Maximum Max ( Expression1 , Expression2 ) Member Expression . Identifier Index Expression [ IndexExpressions ] Call Expression ( Parameters ) Negate - Expression Posate + Expression Bitwise complement ~ Expression Boolean not Not Expression Absolute value Abs Expression Sign Sgn Expression Value byte size SizeOf Expression Variable address Varptr Variable Convert type expression Type Expression Power Expression ^ Expression Multiply Expression * Expression Divide Expression / Expression Remainder Expression Mod Expression Bitwise shift left Expression Shl Expression Bitwise shift right Expression Shr Expression Arithmetic shift right Expression Sar Expression Add Expression + Expression Subtract Expression - Expression Bitwise and Expression & Expression Bitwise or Expression | Expression Bitwise exclusive or Expression ~ Expression Equal Expression = Expression Not equal Expression <> Expression Less than Expression < Expression Greater than Expression > Expression Less than or equal Expression <= Expression Greater than or equal Expression >= Expression Conditional and Expression And Expression Conditional or Expression Or Expression In addition, the following built in functions are also supported: Function Syntax Character code Asc ( Expression ) Character Chr ( Expression ) Value length Len ( Expression ) Null returns 0, an empty string, an empty array, the null object or a pointer to 0 depending on context. True and False are integer constants with the values 1 and 0, respectively. The index operator can be used on either arrays or strings. If used on an array, the element at the specified index is returned. If used on a string, the character code of the character at the specified index is returned. The Not operator 'inverts' the logic of a boolean expression. If the expression evaluates to true, Not returns false and vice versa. Asc returns the character value of the first character of a string, or -1 if the length of the string is 0. Chr constructs a 1 character string with the specified character value. Len can be used with either a string or array. When used with a string, Len returns the number of characters in the string. When used with an array, Len returns the number of elements in the array. In the case of multidimensional arrays, Len returns the total number of elements. Boolean expressions It is frequently necessary to consider an expression as 'true' or 'false', for example, for use with an If statement. The rules for determining whether an expression is true or false are: Expression Type Truth condition Numeric True if value is not equal to 0 Object True if object is not equal to Null String True if length is not equal to 0 Array True if length is not equal to 0