Perl - Revision history

Paul at 11:07, 12 April 2023

2023-04-12T11:07:55Z

← Older revision		Revision as of 11:07, 12 April 2023
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	== Talks ==		== Talks ==

	* [https://www.youtube.com/watch?v=bSd8FwdIALY Perl ~~Optmisization~~ Tidbits] - some surprising results (Perl 5.22, so may no longer be relevant)		* [https://www.youtube.com/watch?v=bSd8FwdIALY Perl Optimisization Tidbits] - some surprising results (Perl 5.22, so may no longer be relevant)
	* [https://www.youtube.com/watch?v=L98dUbVN2Mw Modern Approaches to Ancient Perls]		* [https://www.youtube.com/watch?v=L98dUbVN2Mw Modern Approaches to Ancient Perls]

2023-04-11T15:32:06Z

Talks

← Older revision		Revision as of 15:32, 11 April 2023
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	* [https://www.youtube.com/watch?v=bSd8FwdIALY Perl Optmisization Tidbits] - some surprising results (Perl 5.22, so may no longer be relevant)		* [https://www.youtube.com/watch?v=bSd8FwdIALY Perl Optmisization Tidbits] - some surprising results (Perl 5.22, so may no longer be relevant)
			* [https://www.youtube.com/watch?v=L98dUbVN2Mw Modern Approaches to Ancient Perls]

2023-04-11T14:54:11Z

← Older revision		Revision as of 14:54, 11 April 2023
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	* The <code>qw</code> function allows a list to be generated from elements separated by whitespace, without the need for quotes or commas, e.g. <code>@array = qw(a b c d)</code>.		* The <code>qw</code> function allows a list to be generated from elements separated by whitespace, without the need for quotes or commas, e.g. <code>@array = qw(a b c d)</code>.
	* Array items can either be a scalar value, or a reference to another list. If you use an array in a list (e.g. <code>@list = (@array)</code>), it will be expanded to a scalar value rather than being a reference to the array.		* Array items can either be a scalar value, or a reference to another list. If you use an array in a list (e.g. <code>@list = (@array)</code>), it will be expanded to a scalar value rather than being a reference to the array.

			== Performance ==

			* Scoping hurts performance (but probably improves readability and keeps variables scoped)

	== Talks ==		== Talks ==

	* [https://www.youtube.com/watch?v=bSd8FwdIALY Perl Optmisization Tidbits] - some surprising results (Perl 5.22, so may no longer be relevant)		* [https://www.youtube.com/watch?v=bSd8FwdIALY Perl Optmisization Tidbits] - some surprising results (Perl 5.22, so may no longer be relevant)

2023-04-11T13:43:07Z

← Older revision		Revision as of 13:43, 11 April 2023
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	* The <code>qw</code> function allows a list to be generated from elements separated by whitespace, without the need for quotes or commas, e.g. <code>@array = qw(a b c d)</code>.		* The <code>qw</code> function allows a list to be generated from elements separated by whitespace, without the need for quotes or commas, e.g. <code>@array = qw(a b c d)</code>.
	* Array items can either be a scalar value, or a reference to another list. If you use an array in a list (e.g. <code>@list = (@array)</code>), it will be expanded to a scalar value rather than being a reference to the array.		* Array items can either be a scalar value, or a reference to another list. If you use an array in a list (e.g. <code>@list = (@array)</code>), it will be expanded to a scalar value rather than being a reference to the array.

			== Talks ==

			* [https://www.youtube.com/watch?v=bSd8FwdIALY Perl Optmisization Tidbits] - some surprising results (Perl 5.22, so may no longer be relevant)

2019-09-05T15:38:53Z

Arrays and lists

← Older revision		Revision as of 15:38, 5 September 2019
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	* List ranges can be generated using <code>..</code>, e.g. </code>(1..10)</code> will include the numbers from 1 to 10.		* List ranges can be generated using <code>..</code>, e.g. </code>(1..10)</code> will include the numbers from 1 to 10.
	* The <code>qw</code> function allows a list to be generated from elements separated by whitespace, without the need for quotes or commas, e.g. <code>@array = qw(a b c d)</code>.		* The <code>qw</code> function allows a list to be generated from elements separated by whitespace, without the need for quotes or commas, e.g. <code>@array = qw(a b c d)</code>.
			* Array items can either be a scalar value, or a reference to another list. If you use an array in a list (e.g. <code>@list = (@array)</code>), it will be expanded to a scalar value rather than being a reference to the array.

2019-09-05T15:36:38Z

Arrays and lists

← Older revision		Revision as of 15:36, 5 September 2019
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	* An empty list is represented by <code>()</code>, and an empty array can be initialised as <code>my @array = ();</code>		* An empty list is represented by <code>()</code>, and an empty array can be initialised as <code>my @array = ();</code>
	* List ranges can be generated using <code>..</code>, e.g. </code>(1..10)</code> will include the numbers from 1 to 10.		* List ranges can be generated using <code>..</code>, e.g. </code>(1..10)</code> will include the numbers from 1 to 10.
			* The <code>qw</code> function allows a list to be generated from elements separated by whitespace, without the need for quotes or commas, e.g. <code>@array = qw(a b c d)</code>.

2019-09-05T15:34:04Z

Arrays and lists

← Older revision		Revision as of 15:34, 5 September 2019
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	* Negative array indices start from the end of the list, so the last element can be accessed as <code>$array[-1]</code>.		* Negative array indices start from the end of the list, so the last element can be accessed as <code>$array[-1]</code>.
	* An empty list is represented by <code>()</code>, and an empty array can be initialised as <code>my @array = ();</code>		* An empty list is represented by <code>()</code>, and an empty array can be initialised as <code>my @array = ();</code>
			* List ranges can be generated using <code>..</code>, e.g. </code>(1..10)</code> will include the numbers from 1 to 10.

2019-09-05T15:33:07Z

Arrays and lists

← Older revision		Revision as of 15:33, 5 September 2019
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	* <code>$#array</code> contains the last element index of the array. Since arrays are zero-indexed, the size of the array is <code>$#array + 1</code>.		* <code>$#array</code> contains the last element index of the array. Since arrays are zero-indexed, the size of the array is <code>$#array + 1</code>.
	* Negative array indices start from the end of the list, so the last element can be accessed as <code>$array[-1]</code>.		* Negative array indices start from the end of the list, so the last element can be accessed as <code>$array[-1]</code>.
			* An empty list is represented by <code>()</code>, and an empty array can be initialised as <code>my @array = ();</code>

2019-09-05T15:26:25Z

← Older revision		Revision as of 15:26, 5 September 2019
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	use English;		use English;

			== Arrays and lists ==

			* Although used interchangeably, technically a list is the collection of elements whereas an array is the variable that points to the list.
			* <code>$#array</code> contains the last element index of the array. Since arrays are zero-indexed, the size of the array is <code>$#array + 1</code>.
			* Negative array indices start from the end of the list, so the last element can be accessed as <code>$array[-1]</code>.

2019-09-05T15:13:28Z

Robust scripts

← Older revision		Revision as of 15:13, 5 September 2019
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	use v5.14;		use v5.14;

			More readable names for common variables (e.g. <code>$/</code> can be referred to as <code>$INPUT_RECORD_SEPARATOR</code>) can be created with:

			use English;