- Regex for number with commas dots and parentheses how to#
- Regex for number with commas dots and parentheses code#
Actually, there aren't really functions in this sense, just list operators and unary operators behaving as functions because you put parentheses around the arguments. They include variables, quote and quote-like operators, any expression in parentheses, and any function whose arguments are parenthesized. # Terms and List Operators (Leftward)Ī TERM has the highest precedence in Perl. Many operators can be overloaded for objects. In the following sections, these operators are covered in detail, in the same order in which they appear in the table above. This chaining means that each comparison is performed on the two arguments surrounding it, with each interior argument taking part in two comparisons, and the comparison results are implicitly ANDed. Some comparison operators, as their associativity, chain with some operators of the same precedence (but never with operators of different precedence). A few operators such as &= have special evaluation rules that can result in an operand not being evaluated at all in general, the top-level operator in an expression has control of operand evaluation. In fact Perl has a general rule that the operands of an operator are evaluated in left-to-right order. But the order of operations is not fully determined by this: in 2 * 2 + 4 * 5 both multiplications must be performed before the addition, but the grouping does not say anything about the order in which the two multiplications are performed. For example, in 2 + 4 * 5, the grouping implied by precedence means that the multiplication of 4 and 5 must be performed before the addition of 2 and 20, simply because the result of that multiplication is required as one of the operands of the addition. So the expression yields 6 - 2 = 4, rather than 9 - 1 = 8.įor simple operators that evaluate all their operands and then combine the values in some way, precedence and associativity (and parentheses) imply some ordering requirements on those combining operations. It is as if the expression were written (9 - 3) - 2, not 9 - (3 - 2). For example, in 9 - 3 - 2, subtraction is left associative, so 9 - 3 is grouped together as the left-hand operand of the second subtraction, rather than 3 - 2 being grouped together as the right-hand operand of the first subtraction. Operator associativity defines what happens if a sequence of the same operators is used one after another: usually that they will be grouped at the left or the right.
So the expression yields 2 + 20 = 22, rather than 6 * 5 = 30. It is as if the expression were written 2 + (4 * 5), not (2 + 4) * 5. For example, in 2 + 4 * 5, the multiplication has higher precedence, so 4 * 5 is grouped together as the right-hand operand of the addition, rather than 2 + 4 being grouped together as the left-hand operand of the multiplication. Operator precedence means some operators group more tightly than others. Operator precedence and associativity work in Perl more or less like they do in mathematics. There are a few exceptions though: x can be either string repetition or list repetition, depending on the type of the left operand, and &, |, ^ and ~ can be either string or numeric bit operations. For example $x = $y compares two numbers for equality, and $x eq $y compares two strings. It also means that Perl has two versions of some operators, one for numeric and one for string comparison. This is in contrast to many other dynamic languages, where the operation is determined by the type of the first argument. For example $x + $y is always a numeric addition, and if $x or $y do not contain numbers, an attempt is made to convert them to numbers first.
In Perl, the operator determines what operation is performed, independent of the type of the operands. Perlop - Perl operators and precedence #DESCRIPTION
Regex for number with commas dots and parentheses how to#
I've been trying to figure this out, I read posts on this site, but so far I could not figure out how to do it, I've tried many things but nothing I would appreciate your help in this matter.
Regex for number with commas dots and parentheses code#
Here is an image with marks in red pointing the cuestion:Īnd Here is the code of modification of the author-date BibLaTeX: \usepackage %title non-italic
The components of the books and thesis must be separated by a period, i can separate all components of the references with exception for the separation between inmediate component before a number of pages (publisher, location, etc.) wich is a comma, and must be a dot. I can solve it almost totally with biblatex, only remains one thing. In the references lists, they already have their own requirements too. I'm preparing a thesis style for mi University, they have very particular format requirements as usually.