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diff --git a/share/doc/gdb/Additions-to-Ada.html b/share/doc/gdb/Additions-to-Ada.html new file mode 100644 index 0000000..55a7c98 --- /dev/null +++ b/share/doc/gdb/Additions-to-Ada.html @@ -0,0 +1,199 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. 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In +Ada, this operator is generally not necessary, since its prime use is +in displaying parts of an array, and slicing will usually do this in +Ada. However, there are occasional uses when debugging programs in +which certain debugging information has been optimized away. + +</li><li> <code><var>B</var>::<var>var</var></code> means “the variable named <var>var</var> that +appears in function or file <var>B</var>.” When <var>B</var> is a file name, +you must typically surround it in single quotes. + +</li><li> The expression <code>{<var>type</var>} <var>addr</var></code> means “the variable of type +<var>type</var> that appears at address <var>addr</var>.” + +</li><li> A name starting with ‘<samp>$</samp>’ is a convenience variable +(see <a href="Convenience-Vars.html#Convenience-Vars">Convenience Vars</a>) or a machine register (see <a href="Registers.html#Registers">Registers</a>). +</li></ul> + +<p>In addition, <small>GDB</small> provides a few other shortcuts and outright +additions specific to Ada: +</p> +<ul> +<li> The assignment statement is allowed as an expression, returning +its right-hand operand as its value. Thus, you may enter + +<div class="smallexample"> +<pre class="smallexample">(gdb) set x := y + 3 +(gdb) print A(tmp := y + 1) +</pre></div> + +</li><li> The semicolon is allowed as an “operator,” returning as its value +the value of its right-hand operand. +This allows, for example, +complex conditional breaks: + +<div class="smallexample"> +<pre class="smallexample">(gdb) break f +(gdb) condition 1 (report(i); k += 1; A(k) > 100) +</pre></div> + +</li><li> An extension to based literals can be used to specify the exact byte +contents of a floating-point literal. After the base, you can use +from zero to two ‘<samp>l</samp>’ characters, followed by an ‘<samp>f</samp>’. The +number of ‘<samp>l</samp>’ characters controls the width of the resulting real +constant: zero means <code>Float</code> is used, one means +<code>Long_Float</code>, and two means <code>Long_Long_Float</code>. + +<div class="smallexample"> +<pre class="smallexample">(gdb) print 16f#41b80000# +$1 = 23.0 +</pre></div> + +</li><li> Rather than use catenation and symbolic character names to introduce special +characters into strings, one may instead use a special bracket notation, +which is also used to print strings. A sequence of characters of the form +‘<samp>["<var>XX</var>"]</samp>’ within a string or character literal denotes the +(single) character whose numeric encoding is <var>XX</var> in hexadecimal. The +sequence of characters ‘<samp>["""]</samp>’ also denotes a single quotation mark +in strings. For example, +<div class="smallexample"> +<pre class="smallexample"> "One line.["0a"]Next line.["0a"]" +</pre></div> +<p>contains an ASCII newline character (<code>Ada.Characters.Latin_1.LF</code>) +after each period. +</p> +</li><li> The subtype used as a prefix for the attributes <tt>'Pos</tt>, <tt>'Min</tt>, and +<tt>'Max</tt> is optional (and is ignored in any case). For example, it is valid +to write + +<div class="smallexample"> +<pre class="smallexample">(gdb) print 'max(x, y) +</pre></div> + +</li><li> When printing arrays, <small>GDB</small> uses positional notation when the +array has a lower bound of 1, and uses a modified named notation otherwise. +For example, a one-dimensional array of three integers with a lower bound +of 3 might print as + +<div class="smallexample"> +<pre class="smallexample">(3 => 10, 17, 1) +</pre></div> + +<p>That is, in contrast to valid Ada, only the first component has a <code>=></code> +clause. +</p> +</li><li> You may abbreviate attributes in expressions with any unique, +multi-character subsequence of +their names (an exact match gets preference). +For example, you may use <tt>a'len</tt>, <tt>a'gth</tt>, or <tt>a'lh</tt> +in place of <tt>a'length</tt>. + +</li><li> <a name="index-quoting-Ada-internal-identifiers"></a> +Since Ada is case-insensitive, the debugger normally maps identifiers you type +to lower case. The GNAT compiler uses upper-case characters for +some of its internal identifiers, which are normally of no interest to users. +For the rare occasions when you actually have to look at them, +enclose them in angle brackets to avoid the lower-case mapping. +For example, +<div class="smallexample"> +<pre class="smallexample">(gdb) print <JMPBUF_SAVE>[0] +</pre></div> + +</li><li> Printing an object of class-wide type or dereferencing an +access-to-class-wide value will display all the components of the object’s +specific type (as indicated by its run-time tag). Likewise, component +selection on such a value will operate on the specific type of the +object. + +</li></ul> + +<hr> +<div class="header"> +<p> +Next: <a href="Overloading-support-for-Ada.html#Overloading-support-for-Ada" accesskey="n" rel="next">Overloading support for Ada</a>, Previous: <a href="Omissions-from-Ada.html#Omissions-from-Ada" accesskey="p" rel="previous">Omissions from Ada</a>, Up: <a href="Ada.html#Ada" accesskey="u" rel="up">Ada</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |