String functions

Requires WDL v1.2. Given two String parameters input and pattern, searches for the occurrence of pattern within input and returns the first match or None if there are no matches. pattern is a [regular expression](https://en.wikipedia.org/wiki/Regular_expression) and is evaluated as a [POSIX Extended Regular Expression (ERE)](https://en.wikipedia.org/wiki/Regular_expression#POSIX_basic_and_extended). Note that regular expressions are written using regular WDL strings, so backslash characters need to be double-escaped. For example:

String

the input string to search.

String

the pattern to search for.

returns

The contents of the first match, or None if pattern does not match input.

String? match = find("Hello, world!", "e..o");
# `match` now contains `ello`.

Requires WDL v1.2. Given two String parameters input and pattern, tests whether pattern matches input at least once. pattern is a [regular expression](https://en.wikipedia.org/wiki/Regular_expression) and is evaluated as a [POSIX Extended Regular Expression (ERE)](https://en.wikipedia.org/wiki/Regular_expression#POSIX_basic_and_extended). To test whether pattern matches the entire input, make sure to begin and end the pattern with anchors. For example: Note that regular expressions are written using regular WDL strings, so backslash characters need to be double-escaped. For example:

String

the input string to search.

String

the pattern to search for.

returns

true if pattern matches input at least once, otherwise false.

Boolean matches = matches("sample1234_R1.fastq", "_R1");
# `matches` now contains `true`.

Requires WDL v1.3. Given the two String parameters input and delimiter, this function splits the input string on the provided delimiter and stores the results in a Array[String]. delimiter is a [regular expression](https://en.wikipedia.org/wiki/Regular_expression) and is evaluated as a [POSIX Extended Regular Expression (ERE)](https://en.wikipedia.org/wiki/Regular_expression#POSIX_basic_and_extended). Regular expressions are written using regular WDL strings, so backslash characters need to be double-escaped (e.g., "\\t").

String

the input string.

String

the delimiter to split on as a regular expression.

returns

The parts of the input string split by the delimiter. If the delimiter does not match anything in the input string, an array containing a single entry of the input string is returned.

String input = "a,b,c"
Array[String] parts = split(input, ",")
# `parts` now contains `["a", "b", "c"]`.

String multiline = "line1\nline2\nline3"
Array[String] lines = split(multiline, "\\n")
# `lines` now contains `["line1", "line2", "line3"]`.

Given three String parameters input, pattern, replace, this function replaces all non-overlapping occurrences of pattern in input by replace. pattern is a [regular expression](https://en.wikipedia.org/wiki/Regular_expression) and is evaluated as a [POSIX Extended Regular Expression (ERE)](https://en.wikipedia.org/wiki/Regular_expression#POSIX_basic_and_extended). Regular expressions are written using regular WDL strings, so backslash characters need to be double-escaped (e.g., "\\t").

String

the input string.

String

the pattern to search for.

String

the replacement string.

returns

the input string, with all occurrences of the pattern replaced by the replacement string.

String chocolike = "I like chocolate when\nit's late"
String chocolove = sub(chocolike, "like", "love") #

# `chocolove` now contains `"I love chocolate when\nit's late"`.