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NASA NTRS · 20220010683

Generic Programming in Fortran 202Y

Thomas Clune
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Abstract

Back in 2018, the Fortran committee began planning new features for what is now expected to be Fortran 2023, "generic programming" was at the top of the list of requests from the user community. Here, generic programming refers to the ability to specify algorithms that are parameterized in terms of deferred _types_ (as opposed to values). Concrete algorithms are subsequently generated when the generic algorithms are "instantiated" with specific types. After significant consideration the language committee decided that the necessary changes to Fortran to support generic programming would be too large and complex to complete within a single release cycle of the standard. Instead, a new "generics" subgroup was formed with myself as the lead, and we were charged with developing generic programming features for the subsequent release _after_ the F2023, internally referred to as Fortran 202Y. I.e, the new subgroup was provided the luxury of developing the new capabilities across two full release cycles of the standard. This talk will describe the current approach to generics being pursued by the subgroup as well as the current status halfway through the development cycle. I will conclude with some motivating examples implemented with notional syntax.

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Thomas Clune. Generic Programming in Fortran 202Y. https://ntrs.nasa.gov/citations/20220010683

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