Release calc version 2.10.2t30

help/newerror

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+NAME
+    newerror - create a new error type
+
+SYNOPSIS
+    newerror([str])
+
+TYPES
+    str		non-null string
+
+    return	error-value
+
+DESCRIPTION
+    With or without an argument, newerror() creates an error-value
+    different from already existing error-values.  With the argument
+    str, if x == newerror(str), strerror(iserror(x)) returns str.
+
+EXAMPLE
+    > e1 = newerror("Non-positive side")
+    > e2 = newerror("Non-triangle sides")
+
+    > define area(a,b,c) {\
+    >	local s;\
+    >	if (!(a > 0) || !(b > 0) || !(c > 0)) return e1;\
+    >	s = (a + b + c)/2;\
+    >	if (s <= a || s <= b || s <= c) return e2;\
+    >	return sqrt(s * (s - a) * (s - b) * (s - c)); }
+
+    > print strerror(iserror(area(8,2,5)))
+
+    Non-triangle sides
+
+LIMITS
+    none - XXX - is this correct?
+
+LIBRARY
+    none
+
+SEE ALSO
+    errorcodes, iserror, error