§21.3. Saying lists of values
Any list L can be said:
let L1 be {2, 3, 5, 7, 11};
say L1;
produces the text "2, 3, 5, 7 and 11" - unless we have "Use serial comma." set, in which case a comma appears after the 7. We also have the option of using the more formal notation:
say "[(list of values) in brace notation]"
This text substitution produces the list in the form of "{", then a comma-separated list, and then "}", which looks less like an English sentence but more mathematical. Example:
"[list of people in brace notation]"
might produce "{ yourself, Mr Darcy, Flashman }".
If we say a list of lists, then the individual entry lists are always printed in brace notation: the ordinary sentence way would be incomprehensible.
Of course, the values in L1 are written out in number form because L1 is a list of numbers: we could alternatively try
let L2 be {the piano, the music stand};
say L2;
which produces "piano and music stand". Lists of objects can be said in two additional ways:
say "[(list of objects) with definite articles]"
This text substitution writes out the list in sentence form, adding the appropriate definite articles. Example:
let L be {the piano, the music stand};
say "[L with definite articles]";
says "the piano and the music stand".
say "[(list of objects) with indefinite articles]"
This text substitution writes out the list in sentence form, adding the appropriate indefinite articles. Example:
let L be {the piano, the music stand};
say "[L with definite articles]";
says "a piano and a music stand".
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