Del: Difference between revisions

Jump to navigation Jump to search
No change in size ,  20:30, 24 November 2020
m
no edit summary
(Created page with "{{Glyphbox|∇}} The glyph '''del''' is a triangular symbol resembling an inverted Greek wikipedia:delta (letter) and is represented by the Unicode character <cod...")
 
mNo edit summary
Line 2: Line 2:
The [[glyph]] '''del''' is a triangular symbol resembling an inverted Greek [[wikipedia:delta (letter)|delta]] and is represented by the [[Unicode]] character <code>∇</code>, "nabla". Its uses include:
The [[glyph]] '''del''' is a triangular symbol resembling an inverted Greek [[wikipedia:delta (letter)|delta]] and is represented by the [[Unicode]] character <code>∇</code>, "nabla". Its uses include:
* In [[APL\360]] and most other APLs, it is used to enter and exit the [[wikipedia:line editor]] which provides a function definition mode.<ref>[[Dyalog Ltd.]] Programming Reference Guide. [https://help.dyalog.com/latest/#Language/Defined%20Functions%20and%20Operators/APL%20Line%20Editor.htm APL Line Editor].</ref>
* In [[APL\360]] and most other APLs, it is used to enter and exit the [[wikipedia:line editor]] which provides a function definition mode.<ref>[[Dyalog Ltd.]] Programming Reference Guide. [https://help.dyalog.com/latest/#Language/Defined%20Functions%20and%20Operators/APL%20Line%20Editor.htm APL Line Editor].</ref>
* In [[Dyalog APL]], [[NARS2000]], [[ngn/APL]], and [[dzaima/APL]] <source lang=apl inline>∇</source> represents the current [[dfn]], or the function derived from the current [[dop]], such that anonymous functions and operators may [[wikipedia:recursion (computer science)|recurse]].<ref>[[Dyalog Ltd.]] Programming Reference Guide. [https://help.dyalog.com/latest/#Language/Defined%20Functions%20and%20Operators/DynamicFunctions/Recursion.htm Recursion].</ref>
* In [[Dyalog APL]], [[NARS2000]], [[ngn/apl]], and [[dzaima/APL]] <source lang=apl inline>∇</source> represents the current [[dfn]], or the function derived from the current [[dop]], such that anonymous functions and operators may [[wikipedia:recursion (computer science)|recurse]].<ref>[[Dyalog Ltd.]] Programming Reference Guide. [https://help.dyalog.com/latest/#Language/Defined%20Functions%20and%20Operators/DynamicFunctions/Recursion.htm Recursion].</ref>
* In [[Dyalog APL]], <source lang=apl inline>∇</source> is used to delimit [[tradfn]] members of scripted [[object oriented programming|objects]].<ref>[[Dyalog Ltd.]] Programming Reference Guide. [https://help.dyalog.com/latest/#Language/Object%20Oriented%20Programming/Class%20Members/Methods/Methods.htm Methods].</ref>
* In [[Dyalog APL]], <source lang=apl inline>∇</source> is used to delimit [[tradfn]] members of scripted [[object oriented programming|objects]].<ref>[[Dyalog Ltd.]] Programming Reference Guide. [https://help.dyalog.com/latest/#Language/Object%20Oriented%20Programming/Class%20Members/Methods/Methods.htm Methods].</ref>
* In [[APL2]], [[APLX]], and [[APL*PLUS]], a variant glyph <source lang=apl inline>⍫</source>, consisting of a Del <source lang=apl inline>∇</source> overstruck with a Tilde <source lang=apl inline>~</source>, is used instead of the closing <source lang=apl inline>∇</source> to "lock" the function definition. This prevents viewing or modifying the function's definition while still allowing the function to run. <ref>[[MicroAPL]]. APLX Help. [http://microapl.com/apl_help/ch_020_010_070.htm User-defined Functions].</ref> [[Dyalog APL]] instead offers the [[Lock Definition]] (<source lang=apl inline>⎕LOCK</source>) [[system function]] which provides a more fine-grained management of locked behaviour.<ref>[[Dyalog Ltd.]] Language Reference Guide. [https://help.dyalog.com/latest/#Language/System%20Functions/lock.htmLock Definition].</ref>
* In [[APL2]], [[APLX]], and [[APL*PLUS]], a variant glyph <source lang=apl inline>⍫</source>, consisting of a Del <source lang=apl inline>∇</source> overstruck with a Tilde <source lang=apl inline>~</source>, is used instead of the closing <source lang=apl inline>∇</source> to "lock" the function definition. This prevents viewing or modifying the function's definition while still allowing the function to run. <ref>[[MicroAPL]]. APLX Help. [http://microapl.com/apl_help/ch_020_010_070.htm User-defined Functions].</ref> [[Dyalog APL]] instead offers the [[Lock Definition]] (<source lang=apl inline>⎕LOCK</source>) [[system function]] which provides a more fine-grained management of locked behaviour.<ref>[[Dyalog Ltd.]] Language Reference Guide. [https://help.dyalog.com/latest/#Language/System%20Functions/lock.htmLock Definition].</ref>

Navigation menu