[#BloombergLP-bdlt-ProlepticDateImpUtil-isValidYearDay] = xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bdlt.adoc[bdlt]::xref:BloombergLP/bdlt/ProlepticDateImpUtil.adoc[ProlepticDateImpUtil]::isValidYearDay :relfileprefix: ../../../ :mrdocs: Return `true` if the specified `year` and `dayOfYear` represents a valid date value, and `false` otherwise. Note that valid date values are (as fully defined in the component‐level documentation) in the range `[0001/01 .. 9999/366]`. == Synopsis Declared in `<bdlt_prolepticdateimputil.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- static bool isValidYearDay( int year, int dayOfYear); ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#