Now that the distinction is possible, it is recommended to do that. My original question was directed to the OP, whether it is deliberate.
And they are confusables only to those not accustomed to it. > On 7 Jun 2018, at 12:05, Philippe Verdy <verd...@wanadoo.fr> wrote: > > In my opinion the usual constant is most often shown as "𝜋" (curly serifs, > slightly slanted) in mathematical articles and books (and in TeX), but rarely > as "π" (sans-serif). > > There's a tradition of using handwriting for this symbol on backboards (not > always with serifs, but still often slanted). A notation with the "π" symbol > uses a legacy troundtrip mapping for old OEM charsets on low-resolution text > terminals where it was distinguished from the more common Greek letter which > was enhanced for better readability once old low-resolution terminals were > replaced. "π" looks too much like an Hangul letter or a legacy box-drawing > character and in fact difficult to recognize as the pi constant, but it may > still be found in some plain-text paragraphs of inline mathematical formulas > on screens (for programmers), at low resolution or with small font sizes, > where most text is in sans-serif Latin and not slanted/italicized and not > using an handwritten style. > > If you think about writing a functional programming language using inline > formulas, then the "π" symbol may be ok for the constant, and custom > identifiers for a function would use standard Greek letters (or other > standard scripts for human languages), or would use "pi" in Latin. You would > then write "pi(π)" in that inline formula. For a classic 2D mathematical > layout, you would use "pi(𝜋)" with distinctive but homonegeous styles for > custom variables/function names and for the classic mathematical constant. > > As much as possible you will avoid mixing confusive letters/symbols in that > language. > > Confusion is still possible is you use old texts mixing old Greek letters for > numerals: you would in that case avoid using the Greek letter pi for naming > your custom function, and would reserve the pi letter for the wellknown > constant. But applying distinctive styles will enhance your formulas for > readability.
