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Commit 2ae6bca4 authored by Victor Zverovich's avatar Victor Zverovich
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Complete syntax section

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doc/Text Formatting.html
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......@@ -516,24 +516,24 @@ The meaning of the various alignment options is as follows:
</thead>
<tbody>
<tr>
<td>'&lt;'</td>
<td><code>'&lt;'</code></td>
<td>Forces the field to be left-aligned within the available space (this is
the default for most objects).</td>
</tr>
<tr>
<td>'&gt;'</td>
<td><code>'&gt;'</code></td>
<td>Forces the field to be right-aligned within the available space (this is
the default for numbers).</td>
</tr>
<tr>
<td>'='</td>
<td><code>'='</code></td>
<td>Forces the padding to be placed after the sign (if any) but before the
digits. This is used for printing fields in the form
<code>+000000120</code>. This alignment option is only valid for numeric
types.</td>
</tr>
<tr>
<td>'^'</td>
<td><code>'^'</code></td>
<td>Forces the field to be centered within the available space.</td>
</tr>
</tbody>
......@@ -556,12 +556,12 @@ the following:
</thead>
<tbody>
<tr>
<td>'+'</td>
<td><code>'+'</code></td>
<td>Indicates that a sign should be used for both positive as well as negative
numbers.</td>
</tr>
<tr>
<td>'-'</td>
<td><code>'-'</code></td>
<td>Indicates that a sign should be used only for negative numbers (this is
the default behavior).</td>
</tr>
......@@ -573,7 +573,223 @@ the following:
</tbody>
</table>
<p>TODO</p>
<p>
The <code>'#'</code> option causes the <em>alternate form</em to be used for
the conversion. The alternate form is defined differently for different types.
This option is only valid for integer and floating-point types. For integers,
when binary, octal, or hexadecimal output is used, this option adds the prefix
respective <code>"0b"</code> (<code>"0B"</code>), <code>"0"</code>, or
<code>"0x"</code> (<code>"0X"</code>) to the output value. Whether the prefix
is lower-case or upper-case is determined by the case of the type specifier,
for example, the prefix <code>"0x"</code> is used for the type <code>'x'</code>
and <code>"0X"</code> is used for <code>'X'</code>. For floating-point numbers
the alternate form causes the result of the conversion to always contain a
decimal-point character, even if no digits follow it. Normally, a decimal-point
character appears in the result of these conversions only if a digit follows it.
In addition, for <code>'g'</code> and <code>'G'</code> conversions, trailing
zeros are not removed from the result.
</p>
<p>
<code>width</code> is a decimal integer defining the minimum field width. If
not specified, then the field width will be determined by the content.
</p>
<p>
Preceding the <code>width</code> field by a zero (<code>'0'</code>) character
enables sign-aware zero-padding for numeric types. This is equivalent to a
<code>fill</code> character of <code>'0'</code> with an <code>alignment</code>
type of <code>'='</code>.
</p>
<p>
The <code>precision</code> is a decimal number indicating how many digits should
be displayed after the decimal point for a floating-point value formatted with
<code>'f'</code> and <code>'F'</code>, or before and after the decimal point
for a floating-point value formatted with <code>'g'</code> or <code>'G'</code>.
For non-number types the field indicates the maximum field size - in other
words, how many characters will be used from the field content. The
<code>precision</code> is not allowed for integer, character, Boolean, and
pointer values.
</p>
<p>
Finally, the <code>type</code> determines how the data should be presented.
</p>
<p>The available string presentation types are:</p>
<table>
<thead>
<tr><th>Type</th><th>Meaning</th></tr>
</thead>
<tbody>
<tr>
<td><code>'s'</code></td>
<td>String format. This is the default type for strings and may be omitted.</td>
</tr>
<tr>
<td>none</td>
<td>The same as <code>'s'</code>.</td>
</tr>
</tbody>
</table>
<p>The available character presentation types are:</p>
<table>
<thead>
<tr><th>Type</th><th>Meaning</th></tr>
</thead>
<tbody>
<tr>
<td><code>'c'</code></td>
<td>Character format. This is the default type for characters and may be
omitted.</td>
</tr>
<tr>
<td>none</td>
<td>The same as <code>'c'</code>.</td>
</tr>
</tbody>
</table>
<p>The available integer presentation types are:</p>
<table>
<thead>
<tr><th>Type</th><th>Meaning</th></tr>
</thead>
<tbody>
<tr>
<td><code>'b'</code></td>
<td>Binary format. Outputs the number in base 2. Using the <code>'#'</code>
option with this type adds the prefix <code>"0b"</code> to the output
value.</td>
</tr>
<tr>
<td><code>'B'</code></td>
<td>Binary format. Outputs the number in base 2. Using the <code>'#'</code>
option with this type adds the prefix <code>"0B"</code> to the output
value.</td>
</tr>
<tr>
<td><code>'d'</code></td>
<td>Decimal integer. Outputs the number in base 10.</td>
</tr>
<tr>
<td><code>'o'</code></td>
<td>Octal format. Outputs the number in base 8.</td>
</tr>
<tr>
<td><code>'x'</code></td>
<td>Hex format. Outputs the number in base 16, using lower-case letters for the
digits above 9. Using the <code>'#'</code> option with this type adds the
prefix <code>"0x"</code> to the output value.</td>
</tr>
<tr>
<td><code>'X'</code></td>
<td>Hex format. Outputs the number in base 16, using upper-case letters for the
digits above 9. Using the <code>'#'</code> option with this type adds the
prefix <code>"0X"</code> to the output value.</td>
</tr>
<tr>
<td><code>'n'</code></td>
<td>Number. This is the same as <code>'d'</code>, except that it uses the
current locale setting to insert the appropriate number separator
characters.</td>
</tr>
<tr>
<td>none</td>
<td>The same as <code>'d'</code>.</td>
</tr>
</tbody>
</table>
<p>
Integer presentation types can also be used with character and Boolean values.
Boolean values are formatted using textual representation, either true or false,
if the presentation type is not specified.
</p>
<p>The available presentation types for floating-point values are:</p>
<table>
<thead>
<tr><th>Type</th><th>Meaning</th></tr>
</thead>
<tbody>
<tr>
<td><code>'a'</code></td>
<td>Hexadecimal floating point format. Prints the number in base 16 with prefix
<code>"0x"</code> and lower-case letters for digits above 9. Uses
<code>'p'</code> to indicate the exponent.</td>
</tr>
<tr>
<td><code>'A'</code></td>
<td>Same as <code>'a'</code> except it uses upper-case letters for the prefix,
digits above 9 and to indicate the exponent.</td>
</tr>
<tr>
<td><code>'e'</code></td>
<td>Exponent notation. Prints the number in scientific notation using the
letter <code>'e'</code> to indicate the exponent.</td>
</tr>
<tr>
<td><code>'E'</code></td>
<td>Exponent notation. Same as <code>'e'</code> except it uses an upper-case
<code>'E'</code> as the separator character.</td>
</tr>
<tr>
<td><code>'f'</code></td>
<td>Fixed point. Displays the number as a fixed-point number.</td>
</tr>
<tr>
<td><code>'F'</code></td>
<td>Fixed point. Same as <code>'f'</code>, but converts <code>nan</code> to
<code>NAN</code> and <code>inf</code> to <code>INF</code>.</td>
</tr>
<tr>
<td><code>'g'</code></td>
<td>General format. For a given precision <code>p >= 1</code>, this rounds the
number to <code>p</code> significant digits and then formats the result in
either fixed-point format or in scientific notation, depending on its
magnitude.
A precision of <code>0</code> is treated as equivalent to a precision of
<code>1</code>.</td>
</tr>
<tr>
<td><code>'n'</code></td>
<td>Number. This is the same as <code>'g'</code>, except that it uses the
current locale setting to insert the appropriate number separator
characters.</td>
</tr>
<tr>
<td>none</td>
<td>The same as <code>'g'</code>.</td>
</tr>
</tbody>
</table>
<p>The available presentation types for pointers are:</p>
<table>
<thead>
<tr><th>Type</th><th>Meaning</th></tr>
</thead>
<tbody>
<tr>
<td><code>'p'</code></td>
<td>Pointer format. This is the default type for pointers and may be
omitted.</td>
</tr>
<tr>
<td>none</td>
<td>The same as <code>'p'</code>.</td>
</tr>
</tbody>
</table>
<h3>Class <code>format_error</code></h3>
......
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