or: Alternation

In rebus.base: Core Functionality for the 'rebus' Package

Description

Match one string or another.

Usage

or(..., capture = FALSE)

x %|% y

or1(x, capture = FALSE)

Arguments

...	Character vectors.
capture	A logical value indicating whether or not the result should be captured. See note.
x	A character vector.
y	A character vector.

Value

A character vector representing part or all of a regular expression.

Note

or takes multiple character vector inputs and returns a character vector of the inputs separated by pipes. %|% is an operator interface to this function. or1 takes a single character vector and returns a string collapsed by pipes.

When capture is TRUE, the values are wrapped in a capture group (see capture). When capture is FALSE (the default for or and or1), the values are wrapped in a non-capture group (see token). When capture is NA, (the case for %|%) the values are not wrapped in anything.

References

http://www.regular-expressions.info/alternation.html

See Also

paste

Examples

# or takes an arbitrary number of arguments and groups them without capture
# Notice the recycling of inputs
or(letters, month.abb, "foo")

# or1 takes a single character vector
or1(c(letters, month.abb, "foo")) # Not the same as before!

# Capture the group
or1(letters, capture = TRUE)

# Don't create a group
or1(letters, capture = NA)

# The pipe operator doesn't group
letters %|% month.abb %|% "foo"

# Usage
(rx <- or("dog", "cat", "hippopotamus"))
stringi::stri_detect_regex(c("boondoggle", "caterwaul", "water-horse"), rx)

Example output

<regex> (?:a|Jan|foo)
<regex> (?:b|Feb|foo)
<regex> (?:c|Mar|foo)
<regex> (?:d|Apr|foo)
<regex> (?:e|May|foo)
<regex> (?:f|Jun|foo)
<regex> (?:g|Jul|foo)
<regex> (?:h|Aug|foo)
<regex> (?:i|Sep|foo)
<regex> (?:j|Oct|foo)
<regex> (?:k|Nov|foo)
<regex> (?:l|Dec|foo)
<regex> (?:m|Jan|foo)
<regex> (?:n|Feb|foo)
<regex> (?:o|Mar|foo)
<regex> (?:p|Apr|foo)
<regex> (?:q|May|foo)
<regex> (?:r|Jun|foo)
<regex> (?:s|Jul|foo)
<regex> (?:t|Aug|foo)
<regex> (?:u|Sep|foo)
<regex> (?:v|Oct|foo)
<regex> (?:w|Nov|foo)
<regex> (?:x|Dec|foo)
<regex> (?:y|Jan|foo)
<regex> (?:z|Feb|foo)
<regex> (?:a|b|c|d|e|f|g|h|i|j|k|l|m|n|o|p|q|r|s|t|u|v|w|x|y|z|Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec|foo)
<regex> (a|b|c|d|e|f|g|h|i|j|k|l|m|n|o|p|q|r|s|t|u|v|w|x|y|z)
<regex> a|b|c|d|e|f|g|h|i|j|k|l|m|n|o|p|q|r|s|t|u|v|w|x|y|z
<regex> a|Jan|foo
<regex> b|Feb|foo
<regex> c|Mar|foo
<regex> d|Apr|foo
<regex> e|May|foo
<regex> f|Jun|foo
<regex> g|Jul|foo
<regex> h|Aug|foo
<regex> i|Sep|foo
<regex> j|Oct|foo
<regex> k|Nov|foo
<regex> l|Dec|foo
<regex> m|Jan|foo
<regex> n|Feb|foo
<regex> o|Mar|foo
<regex> p|Apr|foo
<regex> q|May|foo
<regex> r|Jun|foo
<regex> s|Jul|foo
<regex> t|Aug|foo
<regex> u|Sep|foo
<regex> v|Oct|foo
<regex> w|Nov|foo
<regex> x|Dec|foo
<regex> y|Jan|foo
<regex> z|Feb|foo
<regex> (?:dog|cat|hippopotamus)
[1]  TRUE  TRUE FALSE

rebus.base documentation built on May 2, 2019, 5:14 a.m.