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The long-defunct functions ‘Rd_parse()’, ‘anovalist.lm()’, ‘clearNames()’, ‘gammaCody()’, ‘glm.fit.null()’, ‘lm.fit.null()’, ‘lm.wfit.null()’, ‘manglePackageNames()’, ‘mauchley.test()’, ‘package.contents()’, ‘print.coefmat()’, ‘reshapeLong()’, ‘resapeWide()’, ‘tkclose()’, ‘tkcmd()’, ‘tkfile.dir()’, ‘tkfile.tail()’, ‘tkopen()’, ‘tkputs()’, ‘tkread()’, ‘trySilent()’ and ‘zip.file.extract()’ have been removed entirely (but are still documented in the help system).
Expressions involving user defined operators were not always deparsed faithfully (PR#15179), nor were those involving calls to anonymous functions (the latter reported by Hadley Wickham).