Module and tests:
* Map conditions to related signals.
* Make contexts unhashable.
* Eliminate used "default" attribute in exception definitions.
* Eliminate the _filterfunc in favor of a straight list.
Docs:
* Eliminate documented references to conditions that are not signals.
* Eliminate parenthetical notes such as "1/0 --> Inf" which are no
longer true with the new defaults.
diff --git a/Doc/lib/libdecimal.tex b/Doc/lib/libdecimal.tex
index 3b41d6a..b6164fc 100644
--- a/Doc/lib/libdecimal.tex
+++ b/Doc/lib/libdecimal.tex
@@ -66,10 +66,8 @@
A decimal number is immutable. It has a sign, coefficient digits, and an
exponent. To preserve significance, the coefficient digits do not truncate
trailing zeroes. Decimals also include special values such as
-\constant{Infinity} (the result of \samp{1 / 0}), \constant{-Infinity},
-(the result of \samp{-1 / 0}), and \constant{NaN} (the result of
-\samp{0 / 0}). The standard also differentiates \constant{-0} from
-\constant{+0}.
+\constant{Infinity}, \constant{-Infinity}, and \constant{NaN}. The standard
+also differentiates \constant{-0} from \constant{+0}.
The context for arithmetic is an environment specifying precision, rounding
rules, limits on exponents, flags that indicate the results of operations,
@@ -82,9 +80,7 @@
computation. Depending on the needs of the application, some signals may be
ignored, considered as informational, or treated as exceptions. The signals in
the decimal module are: \constant{Clamped}, \constant{InvalidOperation},
-\constant{ConversionSyntax}, \constant{DivisionByZero},
-\constant{DivisionImpossible}, \constant{DivisionUndefined},
-\constant{Inexact}, \constant{InvalidContext}, \constant{Rounded},
+\constant{DivisionByZero}, \constant{Inexact}, \constant{Rounded},
\constant{Subnormal}, \constant{Overflow}, and \constant{Underflow}.
For each signal there is a flag and a trap enabler. When a signal is
@@ -124,7 +120,7 @@
Decimal instances can be constructed from integers, strings or tuples. To
create a Decimal from a \class{float}, first convert it to a string. This
serves as an explicit reminder of the details of the conversion (including
-representation error). Malformed strings signal \constant{ConversionSyntax}
+representation error). Malformed strings signal \constant{InvalidOperation}
and return a special kind of Decimal called a \constant{NaN} which stands for
``Not a number''. Positive and negative \constant{Infinity} is yet another
special kind of Decimal.
@@ -274,10 +270,8 @@
>>> getcontext().trap_enablers.update({Rounded:0, Inexact:0, Subnormal:0})
>>> getcontext()
Context(prec=9, rounding=ROUND_HALF_EVEN, Emin=-999999999, Emax=999999999,
- setflags=[], settraps=['Underflow', 'DecimalException', 'Clamped',
- 'InvalidContext', 'InvalidOperation', 'ConversionSyntax',
- 'DivisionByZero', 'DivisionImpossible', 'DivisionUndefined',
- 'Overflow'])
+ setflags=[], settraps=['Clamped', 'Underflow', 'InvalidOperation',
+ 'DivisionByZero', 'Overflow'])
\end{verbatim}
Applications typically set the context once at the beginning of a program
@@ -320,7 +314,7 @@
The supplied \var{context} or, if not specified, the current context
governs only the handling of malformed strings not conforming to the
- numeric string syntax. If the context traps \constant{ConversionSyntax},
+ numeric string syntax. If the context traps \constant{InvalidOperation},
an exception is raised; otherwise, the constructor returns a new Decimal
with the value of \constant{NaN}.
@@ -730,13 +724,6 @@
reduced to fit by adding zeroes to the coefficient.
\end{classdesc*}
-\begin{classdesc*}{ConversionSyntax}
- Trying to convert a malformed string such as: \code{Decimal('jump')}.
-
- Decimal converts only strings conforming to the numeric string
- syntax. If this signal is not trapped, returns \constant{NaN}.
-\end{classdesc*}
-
\begin{classdesc*}{DecimalException}
Base class for other signals.
\end{classdesc*}
@@ -750,19 +737,6 @@
the inputs to the calculation.
\end{classdesc*}
-\begin{classdesc*}{DivisionImpossible}
- Error performing a division operation. Caused when an intermediate result
- has more digits that the allowed by the current precision. If not trapped,
- returns \constant{NaN}.
-\end{classdesc*}
-
-
-\begin{classdesc*}{DivisionUndefined}
- This is a subclass of \class{DivisionByZero}.
-
- It occurs only in the context of division operations.
-\end{classdesc*}
-
\begin{classdesc*}{Inexact}
Indicates that rounding occurred and the result is not exact.
@@ -771,14 +745,6 @@
to detect when results are inexact.
\end{classdesc*}
-
-\begin{classdesc*}{InvalidContext}
- This is a subclass of \class{InvalidOperation}.
-
- Indicates an error within the Context object such as an unknown
- rounding operation. If not trapped, returns \constant{NaN}.
-\end{classdesc*}
-
\begin{classdesc*}{InvalidOperation}
An invalid operation was performed.
@@ -809,7 +775,6 @@
\class{Rounded} are also signaled.
\end{classdesc*}
-
\begin{classdesc*}{Rounded}
Rounding occurred though possibly no information was lost.
@@ -844,16 +809,11 @@
Overflow(Inexact, Rounded)
Underflow(Inexact, Rounded, Subnormal)
InvalidOperation
- ConversionSyntax
- DivisionImpossible
- DivisionUndefined(InvalidOperation, exceptions.ZeroDivisionError)
- InvalidContext
Rounded
Subnormal
\end{verbatim}
-
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{Working with threads \label{decimal-threads}}