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Maxima identifiers may comprise alphabetic characters, plus the numerals 0
through 9, plus any other character preceded by the backslash \
character.
A numeral may be the first character of an identifier if it is preceded by a backslash. Numerals which are the second or later characters need not be preceded by a backslash.
The alphabetic characters are initially %, _,
and all characters for which the Lisp function ALPHA-CHAR-P returns true.
Characters may be declared alphabetic by the declare function.
If so declared, they need not be preceded by a backslash in an identifier.
Maxima is case-sensitive. The identifiers foo, FOO, and
Foo are distinct. See Lisp and Maxima for more on this point.
A Maxima identifier is a Lisp symbol which begins with a dollar sign $.
Any other Lisp symbol is preceded by a question mark ? when it appears
in Maxima. See Lisp and Maxima for more on this point.
Examples:
(%i1) %an_ordinary_identifier42; (%o1) %an_ordinary_identifier42
(%i2) embedded\ spaces\ in\ an\ identifier; (%o2) embedded spaces in an identifier
(%i3) symbolp (%); (%o3) true
(%i4) [foo+bar, foo\+bar]; (%o4) [foo + bar, foo+bar]
(%i5) [1729, \1729]; (%o5) [1729, 1729]
(%i6) [symbolp (foo\+bar), symbolp (\1729)]; (%o6) [true, true]
(%i7) [is (foo\+bar = foo+bar), is (\1729 = 1729)]; (%o7) [false, false]
(%i8) baz\~quux; (%o8) baz~quux
(%i9) declare ("~", alphabetic);
(%o9) done
(%i10) baz~quux; (%o10) baz~quux
(%i11) [is (foo = FOO), is (FOO = Foo), is (Foo = foo)]; (%o11) [false, false, false]
(%i12) :lisp (defvar *my-lisp-variable* '$foo) *MY-LISP-VARIABLE*
(%i12) ?\*my\-lisp\-variable\*; (%o12) foo
Next: Inequality, Previous: Nouns and Verbs, Up: Expressions [Contents][Index]