In Backus–Naur form, an expression consists of sequences of symbols and/or sequences separated by '|', indicating a choice, the whole being a possible substitution for the symbol on the left. However, this makes the bar unusable as the regular expression "alternative" operator. This is useful when the regular expression contains instances of the more common forward slash ( /) delimiter using a vertical bar eliminates the need to escape all instances of the forward slash. Similarly, the vertical bar may see use as a delimiter for regular expression operations (e.g. It is frequently used because vertical bars are typically uncommon in the data itself. Examples of a pipe-delimited standard data format are LEDES 1998B and HL7. The double vertical bar operator "||" denotes string concatenation in PL/I, standard ANSI SQL, and theoretical computer science (particularly cryptography).Īlthough not as common as commas or tabs, the vertical bar can be used as a delimiter in a flat file. For example: the Unix command grep -E 'fu|bar' matches lines containing 'fu' or 'bar'. In regular expression syntax, the vertical bar again indicates logical or ( alternation).
#LONGER TEXTBAR LATEX CODE#
Since the character was originally not available in all code pages and keyboard layouts, ANSI C can transcribe it in form of the trigraph ?!, which, outside string literals, is equivalent to the | character. Specifically, in C and other languages following C syntax conventions, such as C++, Perl, Java and C#, a | b denotes a bitwise or whereas a double vertical bar a || b denotes a ( short-circuited) logical or. In many programming languages, the vertical bar is used to designate the logic operation or, either bitwise or or logical or. This usage has led to the character itself being called "pipe". The same "pipe" feature is also found in later versions of DOS and Microsoft Windows. Where the output from the grep process is piped to the more process. In most Unix shells (command interpreters), this is represented by the vertical bar character.
#LONGER TEXTBAR LATEX SERIES#
In this way, a series of commands can be "piped" together, giving users the ability to quickly perform complex multi-stage processing from the command line or as part of a Unix shell script ("bash file"). Ī pipe is an inter-process communication mechanism originating in Unix, which directs the output (standard out and, optionally, standard error) of one process to the input (standard in) of another.
# => long right double arrow (have to enter math mode) # long right arrow (have to enter math mode) # => right double arrow (have to enter math mode) >=!.backslash.!textrightarrow!.braceleft.!!.braceright.! # - Spaced em dashes (entity reference -)
# I needed to rewrite some regular expressions because '' have not been escaped to '<' and '>'Subsnormal=quotes,specialwords,replacements,attributes,macros,specialcharacters,replacements2 # Hence only "callouts" substitution should be applied. # The listing block uses a LaTeX verbatim environment where special characters don't need to be escaped. Subs=quotes,replacements,attributes,macros,specialcharacters,replacements2 # Modifications to fit the latex-tufte styles by Martin Horauer. # Originally created by Benjamin Klum, later modified by Geoff Eddy. # latex backend, generates LaTeX conformant markup.
0 kommentar(er)
