Release calc version 2.10.2t30

help/expression

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+Expression sequences
+
+    This is a sequence of statements, of which expression statements
+    are the commonest case.  Statements are separated with semicolons,
+    and the newline character generally ends the sequence.  If any
+    statement is an expression by itself, or is associated with an
+    'if' statement which is true, then two special things can happen.
+    If the sequence is executed at the top level of the calculator,
+    then the value of '.' is set to the value of the last expression.
+    Also, if an expression is a non-assignment, then the value of the
+    expression is automatically printed if its value is not NULL.
+    Some operations such as	pre-increment and plus-equals are also
+    treated as assignments.
+
+    Examples of this are the following:
+
+    expression		    sets '.' to		prints
+    ----------		    -----------		------
+    3+4				7		   7
+    2*4; 8+1; fact(3)		6		8, 9, and 6
+    x=3^2			9		   -
+    if (3 < 2) 5; else 6	6		   6
+    x++				old x		   -
+    print fact(4)		-		   24
+    null()			null()		   -
+
+    Variables can be defined at the beginning of an expression sequence.
+    This is most useful for local variables, as in the following example,
+    which sums the square roots of the first few numbers:
+
+    local s, i; s = 0; for (i = 0; i < 10; i++) s += sqrt(i); s
+
+    If a return statement is executed in an expression sequence, then
+    the result of the expression sequence is the returned value.  In
+    this case, '.' is set to the value, but nothing is printed.