Nushell Niceties: Checking String Starts Or Ends With Given String

To check if a string value starts or ends with a given string you can use the str starts-with and str ends-with commands. The command returns a boolean value: true if the string starts or ends with the given string and false otherwise. The commands are case sensitive by default. You can use the --ignore-case (or the shorthand -i) to ignore casing while checking if a the string starts or ends with a given string.
To input can be a string value and then that string value is checked. If the input is an array of string values, then each element is checked. It is also possible to check values in a record or table. You need to pass the names of the field(s) or column(s) that you want to check the string values of.

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Nushell Niceties: Tables With Different Themes

A lot of commands have output displayed as table. It is possible to use different themes for tables. If you run the command table --list you get all available themes. At the moment the following themes are available: basic, compact, compact_double, default, heavy, light, none, reinforced, rounded, thin, with_love, psql, markdown, dots, restructured, ascii_rounded, basic_compact, single, double. You can use a theme with the table command by using the --theme option and the name of the theme. For example to have a different table theme for the ls command you can use ls | table --theme light.
If you want to change the theme for all table output you can set the configuration option $env.config.table.mode. To make this configuration setting permanent you can add it to config.nu file.

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Nushell Niceties: Summon Ellie The Nushell Mascot

When you start Nushell you can see a nice ASCII art elephant. That is Ellie a cute and friendly elephant mascot for Nushell. Elephants are popular as you can see them in other products like Mastodon and Gradle. It is possible to summon Ellie in your Nushell environment by running the ellie command. This command is part of the std library and you need to run use std ellie or std use * first.

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Nushell Niceties: Checking For Emptiness

To check if a value is empty you can use the is-empty command. The command can be used for string values, lists and records.
The opposite check to see if a value is not empty can be done with the is-not-empty command. Just like with the is-empty command this can be used for string values, lists and records. To check if values in a table column are not empty the names of the columns to check can be passed as argument.

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Nushell Niceties: Getting Column And Key Names

To get the names of columns in a table or the keys of a record you can use the columns command. The command returns a list of string values that are the column or key names. When the input is table the column names are returned, and when the input is a record the names of the keys are returned.

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Nushell Niceties: Create Query Parameters For URL

The build-in HTTP client in Nushell can be used to interact with REST APIs and websites. If the URL you want to invoke has query parameters than you can use the url build-query command. The url build-query command transforms a record or table to URL encoded key/value pairs joined with an ampersand (&). Each key and value is separated by an equal sign (=). The command can expand a key with a list value to separate key/value pairs with the same key if the key is defined in a record.

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Nushell Niceties: Joining Values Into String

The string module contains a lot of useful commands to work with strings. If you want to join several values from a list into a single string you can use the str join command. The command accepts as argument the character(s) to use for joining the values. If you don't specify the character(s) as argument the default value '' (empty string) is used.

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Nushell Niceties: Encoding And Decoding URL

Sometimes you want to transform a string value into a URL encoded value, so it can be used as part of a valid URL. For example a string with spaces or special characters can not be used in a URL as is, but needs to be URL encoded. Nushell has the url encode command to achieve this. You can simple run this command on a string value and the result is a URL encoded value. With the option --all or -a even more special characters like a dot (.) are encoded. The input of the command can be a string value or a list of string values. But it is also possible to use a record or table structure, but then you need to add as extra argument the name or names of the keys or columns of which the string values should be encoded.
Oppossed to URL encoding a value you can also decode a URL encoded value using the url decode command. This command doesn’t have a special option to run. Just like with the url encode command the url decode command works on strings, list of strings, records and tables. If the input is a record or table the name of key or column of which the values must be decoded must be passed as extra arguments.

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Groovy Goodness: Interleaving Elements From Collections

Groovy 5 adds the interleave method to the Iterable class. With this method you can interleave elements from two iterables. The result is a new List with elements where the first element is the first element of the first iterable and the second element the first element of the second iterable and so on. The size of the smallest collection is used to keep interleaving elements. Elements from the larger collection are ignored in the result.
If you want to have the items from the largest collection in the resulting list you can use the value true as second argument for the interleave method.

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Groovy Goodness: Grouping Iterables Using zip And zipAll

Groovy 5 adds the extension methods zip and zipAll for iterables and iterators. Using the method you can combine elements from two collections into a new collection. The new collection contains Tuple2 instances where the values come from the items at the same index from both collections. So the first item of the first collection is grouped with the first item of the second collection. The size of the resulting collection is determined by the size of the smallest collection that is zipped.
With the zipAll method you can combine iterables of different sizes and set default values for missing items. It is possible to set a default value if an item is missing from the first iterable or the second iterable.

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