Perl Best Practices [Electronic resources] نسخه متنی

B.5. Chapter 6, Control Structures

• Use block if, not postfix if. [If Blocks ]

• Reserve postfix if for flow-of-control statements. [Postfix Selectors ]

• Don't use postfix unless, for, while, or until. [Other Postfix Modifiers ]

• Don't use unless or until at all. [Negative Control Statements ]

• Avoid C-style for statements. [C-Style Loops ]

• Avoid subscripting arrays or hashes within loops. [Unnecessary Subscripting ]

• Never subscript more than once in a loop. [Necessary Subscripting ]

• Use named lexicals as explicit for loop iterators. [Iterator Variables ]

• Always declare a for loop iterator variable with my. [Non-Lexical Loop Iterators ]

• Use map instead of for when generating new lists from old. [List Generation ]

• Use grep and first instead of for when searching for values in a list. [List Selections ]

• Use for instead of map when transforming a list in place. [List Transformation ]

• Use a subroutine call to factor out complex list transformations. [Complex Mappings ]

• Never modify $_ in a list function. [List Processing Side Effects ]

• Avoid cascading an if. [Multipart Selections ]

• Use table look-up in preference to cascaded equality tests. [Value Switches ]

• When producing a value, use tabular ternaries. [Tabular Ternaries ]

• Don't use do...while loops. [do-while Loops ]

• Reject as many iterations as possible, as early as possible. [Linear Coding ]

• Don't contort loop structures just to consolidate control. [Distributed Control ]

• Use for and redo instead of an irregularly counted while. [Redoing ]

• Label every loop that is exited explicitly, and use the label with every next, last, or redo. [Loop Labels ]