083. Propagation of an optional argument

topic: Procedures

Note

This tip is a draft1.

A procedure with an OPTIONAL argument can call a procedure with that argument if it is OPTIONAL there too. The PRESENT status of the argument propagates to called procedures. The optval function of the Fortran stdlib project exploits this.

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A procedure with an OPTIONAL argument can call a procedure with that argument if it is OPTIONAL there too. The PRESENT status of the argument propagates to called procedures. The optval function of the Fortran stdlib project exploits this. pic.twitter.com/amhSL1cbY7

— FortranTip (@fortrantip) January 8, 2022

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1

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