The intersect command can be used on lists and tables to find the same elements that are in the input list or table and a provided list or table.
The input is passed to the command and the other list or table is an argument for the intersect command.
Since Nushell 0.114.0 you can use the random pass command to generate a random password of 12 characters.
Nushell will use a combination of letters, numbers and symbols.
It is possible to generate a password with a different length using the command-line option --chars (or -c) followed by the size of the password.
The minimal length is 4 characters and the maximum size is 128 characters.
If you don’t want to include symbols then you must use the option --no-symbols (or -s).
To exclude numbers the option --no-numbers or short-hand -n must be used.
And finally to exclude lowercase characters use --no-lowercase (or -l) and to exclude uppercase characters use --no-uppercase (or -u).
To support a requirement that at least one character, one number and one symbol is needed the option --require-each-type must be used.
By default Nushell will not use the ambiguous characters 0, O, 1 and l in the same password, because it can be hard to read the differences between the characters with some fonts.
In order to use these characters in the same generated password you must the option --include-ambiguous.
Also the characters i, 1 and l are not used together, but if you specify the option --include-similar these characters can be used in the same generated password.
The def keyword in Nushell is used to define a custom command.
By adding the --wrapped flag you can tell Nushell to accept unknown flags and arguments and pass them on as strings.
In the command parameters you use a "rest" parameter defined by … to capture the remaining arguments.
Then in the command body you use the spread operator … to expand them again.
This is very useful when you want to create a small wrapper around an external command with lots of options, but without having to define all those options yourself.
Kotlin adds the substringBefore, substringBeforeLast, substringAfter and
substringAfterLast extension functions to the String class.
Instead of using indices to get a substring you can use a string or character value.
The functions without Last use the first occurrence of the delimiter and the
methods with Last use the last occurrence.
If the delimiter is not found the original string is returned.
You can supply a value that should be returned when the delimiter is not found.
Kotlin has very useful extensions functions for working with collections.
These extension functions make working with collections more easy and fun.
One of the extension functions is the random function.
When you call random() Kotlin returns a single element from the collection using the default random source.
The function also accepts a Random instance as argument.
This instance has a seeded value to return repeatable random values.
Sometimes you want to transform only the keys in a Map, or only transform the values.
Kotlin has two useful methods to achieve this: mapKeys and mapValues.
You can use mapKeys to transform the keys of the map while keeping the values the same.
With mapValues you can transform the values of the map while keeping the keys the same.
Both methods accept a lambda function as asrgument of type Map.Entry and must return the new key or value.
In order to transform the keys or values and add the result to an existing Map you can use the methods mapKeysTo and mapValuesTo.
The first argument is the existing (mutable) Map and the second argument is the lambda function.
In a previous blogpost you can learn about the semver command in Nushell to transform a string value into a semver type.
The command has a subcommand match-req.
You can use this command to check if a version matches part of the semantic version parts.
The result is a boolean value.
The version to compare with doesn’t have to defined fully, but could exist of only the major, minor or patch parts.
The value you pass can also be used to check if a version is greater or smaller than a given version.
A range with a lower and upper version to match on can be defined as well.
The boundary values are separated by a comma.
The semver Nushell plugin can be used to work with string values as semver type as you can see in a previous post.
You can use the semver sort command to sort string values with ordering rules for semantic versions.
With natural ordering of string values a value of 10.0.1 is placed before 2.1.0, but if you use semver sort the ordering will be correct.
The command will look at all the parts of the semver type.
So a major version of 2 is placed before 10.
If the major version part is the same than the minor part is used for ordering and so on.
To sort in descending order you can use the option --reverse or the short option -r.
In a previous blogpost you can learn about the semver command in Nushell to transform a string value into a semver type.
With the semver bump command you can increase one of the components of the semver type.
For example to increase the major version part you can use semver bump major.
This command will also update the minor and patch parts if needed.
The result is a semver type and you can use into value to transform it to a string type.
Nushell can be extended with plugins to have more functionality or types that are not part of standard Nushell.
If you want to work with string values that are actually semantic version values (https://semver.org) you can use the Nushell SemVer plugin.
The plugin must be added to Nushell by using the command plugin add <location of plugin>.
You can check with plugin list command if the plugin is available.
This command also shows commands that the plugin adds to Nushell.
The command into semver can be used to convert string values into a semver type.
The semver type has 5 properties: major, minor, patch, pre and build.
You can use dot notation to get the values for these properties or use the get command.
In the following command a string value is transformed to a semver type: let v = '4.0.2' | into semver.
And with $v.major you can extract the major part of the semver value and it returns 4.
Records with the keys major, minor, patch, pre and build can be transformed to a semver string with the semver from-record command.
And to transform a semver type to a record you can use the command semver into-record.