LR(0) Automaton for dragon_ptr.gram</tite> <link rel="stylesheet" rev="stylesheet" href="gram.css"> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/> </head> <body> <a href="index.html">Index</a><br /> <div><h1>BNF for <a href="dragon_ptr.gram">dragon_ptr.gram</a></h1><pre width="40%">S := L '=' R | R L := '*' R | 'id' R := L </pre><p>This is a grammar from the Dragon book, it resembles the C pointer dereferencing and assignment syntax. It shows well that it is not a SLR(1) grammar but a LALR(1) grammar.</p> </div> <div> <h1>LR(0) Automaton</h1> <div style="margin-left: 3em"><a href="dragon_ptr.gram.slr.graph.png"><img src="dragon_ptr.gram.slr.graph.tb.png" alt="LR(0) Automaton" /></a><br/> <a href="dragon_ptr.gram.slr.graph.ps">As Postscript</a><br/> <a href="dragon_ptr.gram.slr.dot">As Graphviz DOT</a><br/> </div> </div> <h1>SLR(1) Parser Table</h1> <div style="margin-left: 3em"><h2>Rules:</h2> <table class="data"> <tr><th> 1</th><td>S := L '=' R </td></tr> <tr><th> 2</th><td>S := R </td></tr> <tr><th> 3</th><td>L := '*' R </td></tr> <tr><th> 4</th><td>L := 'id' </td></tr> <tr><th> 5</th><td>R := L </td></tr> </table> <h2>Parser Table:</h2> <table class="data"> <tr><th>State</th><th colspan="4">ACTIONS</th><th colspan="3">GOTO</th></tr><tr><th> </th><th> id</th><th>=</th><th>*</th><th>$</th><th>L</th><th>R</th><th>S</th></tr> <tr><th>0</th><td>s4</td><td> </td><td>s1</td><td> </td><td>5</td><td>2</td><td>3</td> </tr> <tr><th>1</th><td>s4</td><td> </td><td>s1</td><td> </td><td>7</td><td>6</td><td> </td> </tr> <tr><th>2</th><td> </td><td> </td><td> </td><td>r2</td><td> </td><td> </td><td> </td> </tr> <tr><th>3</th><td> </td><td> </td><td> </td><td>A</td><td> </td><td> </td><td> </td> </tr> <tr><th>4</th><td> </td><td>r4</td><td> </td><td>r4</td><td> </td><td> </td><td> </td> </tr> <tr><th>5</th><td> </td><td>s8</td><td> </td><td>r5</td><td> </td><td> </td><td> </td> </tr> <tr><td> </td><td> </td><td>r5</td><td> </td><td> </td><td> </td><td> </td><td> </td> </tr><tr><th>6</th><td> </td><td>r3</td><td> </td><td>r3</td><td> </td><td> </td><td> </td> </tr> <tr><th>7</th><td> </td><td>r5</td><td> </td><td>r5</td><td> </td><td> </td><td> </td> </tr> <tr><th>8</th><td>s4</td><td> </td><td>s1</td><td> </td><td>7</td><td>9</td><td> </td> </tr> <tr><th>9</th><td> </td><td> </td><td> </td><td>r1</td><td> </td><td> </td><td> </td> </tr> </table> </div> <div> <h1>LR(0) Automaton with Lookahead</h1> <div style="margin-left: 3em"><a href="dragon_ptr.gram.lalr.graph.png"><img src="dragon_ptr.gram.lalr.graph.tb.png" alt="LR(0) Automaton with Lookahead" /></a><br/> <a href="dragon_ptr.gram.lalr.graph.ps">As Postscript</a><br/> <a href="dragon_ptr.gram.lalr.dot">As Graphviz DOT</a><br/> </div> </div> <h1>LALR(1) Parser Table</h1> <div style="margin-left: 3em"><h2>Rules:</h2> <table class="data"> <tr><th> 1</th><td>S := L '=' R </td></tr> <tr><th> 2</th><td>S := R </td></tr> <tr><th> 3</th><td>L := '*' R </td></tr> <tr><th> 4</th><td>L := 'id' </td></tr> <tr><th> 5</th><td>R := L </td></tr> </table> <h2>Parser Table:</h2> <table class="data"> <tr><th>State</th><th colspan="4">ACTIONS</th><th colspan="3">GOTO</th></tr><tr><th> </th><th> id</th><th>=</th><th>*</th><th>$</th><th>L</th><th>R</th><th>S</th></tr> <tr><th>0</th><td>s4</td><td> </td><td>s1</td><td> </td><td>5</td><td>2</td><td>3</td> </tr> <tr><th>1</th><td>s4</td><td> </td><td>s1</td><td> </td><td>7</td><td>6</td><td> </td> </tr> <tr><th>2</th><td> </td><td> </td><td> </td><td>r2</td><td> </td><td> </td><td> </td> </tr> <tr><th>3</th><td> </td><td> </td><td> </td><td>A</td><td> </td><td> </td><td> </td> </tr> <tr><th>4</th><td> </td><td>r4</td><td> </td><td>r4</td><td> </td><td> </td><td> </td> </tr> <tr><th>5</th><td> </td><td>s8</td><td> </td><td>r5</td><td> </td><td> </td><td> </td> </tr> <tr><th>6</th><td> </td><td>r3</td><td> </td><td>r3</td><td> </td><td> </td><td> </td> </tr> <tr><th>7</th><td> </td><td>r5</td><td> </td><td>r5</td><td> </td><td> </td><td> </td> </tr> <tr><th>8</th><td>s4</td><td> </td><td>s1</td><td> </td><td>7</td><td>9</td><td> </td> </tr> <tr><th>9</th><td> </td><td> </td><td> </td><td>r1</td><td> </td><td> </td><td> </td> </tr> </table> </div> </body> </html>