上游充通大 ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY Names (identifier) 。Rule: Every identifier must begin with a letter or underscore (")followed by any sequence of letters,digits,or underscores. ·Reserved word Words used in controls:if,else,try... -Words used to specify:global,class Types are not reserved word list,float
Names (identifier) • Rule: – Every identifier must begin with a letter or underscore (“_”), followed by any sequence of letters, digits, or underscores. • Reserved word – Words used in controls: if, else, try… – Words used to specify: global, class • Types are not reserved word – list, float…
上游充通大 ParisTech SHANGHAI JIAO TONG UNIVERSITY INSTITUT DES SCIENCES ET TECHNOLOGIES PARIS INSTITUTE OF TECHNOLOGY Order of the execution Operations Low Operator Description (from lowest precedences to highest precedences lambda Lambda expression or Boolean OR and Boolean AND not x Boolean NOT 1n,not1n,18,1snot,<,=,>,>=,◇，1=，= Comparisons,including membership tests and identity tests, Bitwise OR A Bitwise XOR Bitwise AND <<,>> Shifts Addition and subtraction *,1,/1,8 Multiplication,division,remainder +X-X ~X Positive,negative,bitwise NOT ★女 Exponentiation x[index],x[index:index],x(arguments...),x.attribute Subscription,slicing,call,attribute reference High (expressions...),[expressions...],(key:datum...},expressions... Binding or tuple display,list display,dictionary display,string conversion
Order of the execution Operations Low High