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Release calc version 2.10.3t5.45

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Landon Curt Noll
1997-10-04 20:06:29 -07:00
parent 4618313a82
commit 6e10e97592
300 changed files with 38279 additions and 8584 deletions
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65
help/newerror
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@@ -1,39 +1,70 @@
NAME
newerror - create a new error type
newerror - create or recall a described error-value
SYNOPSIS
newerror([str])
TYPES
str non-null string
str 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.
If str is not "" and has not earlier been used as an argument for
this function, newerror(str) creates a new described error-value so
that any future use of newerror(str) with the same str will return
the same error-value.
If x = newerror(str), both strerror(x) and strerror(iserro(x)) will
return str and iserror(x) will return the error code value of the
new error.
The null cases newerror() and newerror("") are equivalent to
newerror("???").
EXAMPLE
> e1 = newerror("Non-positive side")
> e2 = newerror("Non-triangle sides")
Note that by default, errmax() is 0 so unless errmax() is
increased you will get:
> 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)); }
> ba = newerror("curds n' whey");
Error 20000 caused errcount to exceed errmax
> print strerror(iserror(area(8,2,5)))
> errmax(errcount()+5)
0
> e1 = newerror("triangle side length <= 0")
> iserror(e1)
20000
> error(20000)
Error 20000
> strerror(error(20000))
"triangle side length <= 0"
> strerror(e1);
"triangle side length <= 0"
> strerror(error(iserror(e1)))
"triangle side length <= 0"
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 newerror("Non-triangle sides");
>> return sqrt(s * (s - a) * (s - b) * (s - c));
>> }
"area" defined
> A = area(8,2,5);
> if (iserror(A)) print strerror(A) : ":", iserror(A);
Non-triangle sides: 20001
> A = area(-3,4,5)
> if (iserror(A)) print strerror(A) : ":", iserror(A);
triangle side length <= 0: 20000
LIMITS
none - XXX - is this correct?
The number of new described error-values is not to exceed 12767.
LIBRARY
none
SEE ALSO
errorcodes, iserror, error
errmax, errcount, error, strerror, iserror, errno, errorcodes