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-rw-r--r--system/doc/reference_manual/expressions.xml40
1 files changed, 23 insertions, 17 deletions
diff --git a/system/doc/reference_manual/expressions.xml b/system/doc/reference_manual/expressions.xml
index 497d7eb464..d564b20ca6 100644
--- a/system/doc/reference_manual/expressions.xml
+++ b/system/doc/reference_manual/expressions.xml
@@ -4,7 +4,7 @@
<chapter>
<header>
<copyright>
- <year>2003</year><year>2011</year>
+ <year>2003</year><year>2012</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -561,11 +561,15 @@ number &lt; atom &lt; reference &lt; fun &lt; port &lt; pid &lt; tuple &lt; list
<p>Lists are compared element by element. Tuples are ordered by
size, two tuples with the same size are compared element by
element.</p>
- <p>If one of the compared terms is an integer and the other a
- float, the integer is first converted into a float, unless the
- operator is one of =:= and =/=. If the integer is too big to fit
- in a float no conversion is done, but the order is determined by
- inspecting the sign of the numbers.</p>
+ <p>When comparing an integer to a float, the term with the lesser
+ precision will be converted into the other term's type, unless the
+ operator is one of =:= or =/=. A float is more precise than
+ an integer until all significant figures of the float are to the left of
+ the decimal point. This happens when the float is larger/smaller than
+ +/-9007199254740992.0. The conversion strategy is changed
+ depending on the size of the float because otherwise comparison of large
+ floats and integers would lose their transitivity.</p>
+
<p>Returns the Boolean value of the expression, <c>true</c> or
<c>false</c>.</p>
<p>Examples:</p>
@@ -681,7 +685,7 @@ Expr1 <input>op</input> Expr2</pre>
8> <input>2#10 bor 2#01.</input>
3
9> <input>a + 10.</input>
-** exception error: bad argument in an arithmetic expression
+** exception error: an error occurred when evaluating an arithmetic expression
in operator +/2
called as a + 10
10> <input>1 bsl (1 bsl 64).</input>
@@ -879,9 +883,8 @@ Ei = Value |
and UTF-32, respectively.</p>
<p>When constructing a segment of a <c>utf</c> type, <c>Value</c>
- must be an integer in one of the ranges 0..16#D7FF,
- 16#E000..16#FFFD, or 16#10000..16#10FFFF
- (i.e. a valid Unicode code point). Construction
+ must be an integer in the range 0..16#D7FF or
+ 16#E000....16#10FFFF. Construction
will fail with a <c>badarg</c> exception if <c>Value</c> is
outside the allowed ranges. The size of the resulting binary
segment depends on the type and/or <c>Value</c>. For <c>utf8</c>,
@@ -896,14 +899,13 @@ Ei = Value |
<c><![CDATA[<<$a/utf8,$b/utf8,$c/utf8>>]]></c>.</p>
<p>A successful match of a segment of a <c>utf</c> type results
- in an integer in one of the ranges 0..16#D7FF, 16#E000..16#FFFD,
- or 16#10000..16#10FFFF
- (i.e. a valid Unicode code point). The match will fail if returned value
+ in an integer in the range 0..16#D7FF or 16#E000..16#10FFFF.
+ The match will fail if returned value
would fall outside those ranges.</p>
<p>A segment of type <c>utf8</c> will match 1 to 4 bytes in the binary,
if the binary at the match position contains a valid UTF-8 sequence.
- (See RFC-2279 or the Unicode standard.)</p>
+ (See RFC-3629 or the Unicode standard.)</p>
<p>A segment of type <c>utf16</c> may match 2 or 4 bytes in the binary.
The match will fail if the binary at the match position does not contain
@@ -991,15 +993,19 @@ fun Module:Name/Arity</pre>
<pre>
fun (Arg1,...,ArgN) -> Name(Arg1,...,ArgN) end</pre>
<p>In <c>Module:Name/Arity</c>, <c>Module</c> and <c>Name</c> are atoms
- and <c>Arity</c> is an integer.
+ and <c>Arity</c> is an integer. Starting from the R15 release,
+ <c>Module</c>, <c>Name</c>, and <c>Arity</c> may also be variables.
A fun defined in this way will refer to the function <c>Name</c>
- with arity <c>Arity</c> in the <em>latest</em> version of module <c>Module</c>.
+ with arity <c>Arity</c> in the <em>latest</em> version of module
+ <c>Module</c>. A fun defined in this way will not be dependent on
+ the code for module in which it is defined.
</p>
<p>When applied to a number N of arguments, a tuple
<c>{Module,FunctionName}</c> is interpreted as a fun, referring
to the function <c>FunctionName</c> with arity N in the module
<c>Module</c>. The function must be exported.
- <em>This usage is deprecated.</em>
+ <em>This usage is deprecated.</em> Use <c>fun Module:Name/Arity</c>
+ instead.
See <seealso marker="#calls">Function Calls</seealso> for an example.</p>
<p>More examples can be found in <em>Programming Examples</em>.</p>
</section>