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remove String regex fns
author Franklin Schmidt <fschmidt@gmail.com>
date Fri, 29 Jul 2022 14:12:01 -0600
parents 5c69d2e8bd75
children ba43135bb98d
comparison
equal deleted inserted replaced
1721:5c69d2e8bd75 1722:7d2ab44f7a59
2483 Note that Java's <code>String.format</code> is too stupid to convert between ints and floats, so you must provide the right kind of number. 2483 Note that Java's <code>String.format</code> is too stupid to convert between ints and floats, so you must provide the right kind of number.
2484 </p> 2484 </p>
2485 <% 2485 <%
2486 end 2486 end
2487 } 2487 }
2488 ["String.gmatch"] = {
2489 title = "<code>String.gmatch (s, pattern)</code>"
2490 content = function()
2491 %>
2492 <p>
2493 Returns an iterator function that,
2494 each time it is called,
2495 returns the next captures from <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>)
2496 over the string <code>s</code>.
2497 If <code>pattern</code> specifies no captures,
2498 then the whole match is produced in each call.
2499 </p>
2500
2501 <p>
2502 As an example, the following loop
2503 will iterate over all the words from string <code>s</code>,
2504 printing one per line:
2505 </p>
2506 <pre>
2507 local s = "hello world from Lua"
2508 for w in String.gmatch(s, [[\w+]]) do
2509 print(w)
2510 end
2511 </pre>
2512
2513 <p>
2514 The next example collects all pairs <code>key=value</code> from the
2515 given string into a table:
2516 </p>
2517 <pre>
2518 local t = {}
2519 local s = "from=world, to=Lua"
2520 for k, v in String.gmatch(s, [[(\w+)=(\w+)]]) do
2521 t[k] = v
2522 end
2523 </pre>
2524
2525 <p>
2526 For this function, a caret '<code>^</code>' at the start of a pattern does not
2527 work as an anchor, as this would prevent the iteration.
2528 </p>
2529 <%
2530 end
2531 }
2532 ["String.gsub"] = {
2533 title = "<code>String.gsub (s, pattern, repl [, n])</code>"
2534 content = function()
2535 %>
2536 <p>
2537 Returns a copy of <code>s</code>
2538 in which all (or the first <code>n</code>, if given)
2539 occurrences of the <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) have been
2540 replaced by a replacement string specified by <code>repl</code>,
2541 which can be a string, a table, or a function.
2542 <code>gsub</code> also returns, as its second value,
2543 the total number of matches that occurred.
2544 The name <code>gsub</code> comes from <em>Global SUBstitution</em>.
2545 </p>
2546
2547 <p>
2548 If <code>repl</code> is a string, then its value is used for replacement.
2549 The character&nbsp;<code>\</code> works as an escape character.
2550 Any sequence in <code>repl</code> of the form <code>$<em>d</em></code>,
2551 with <em>d</em> between 1 and 9,
2552 stands for the value of the <em>d</em>-th captured substring.
2553 The sequence <code>$0</code> stands for the whole match.
2554 </p>
2555
2556 <p>
2557 If <code>repl</code> is a table, then the table is queried for every match,
2558 using the first capture as the key.
2559 </p>
2560
2561 <p>
2562 If <code>repl</code> is a function, then this function is called every time a
2563 match occurs, with all captured substrings passed as arguments,
2564 in order.
2565 </p>
2566
2567 <p>
2568 In any case,
2569 if the pattern specifies no captures,
2570 then it behaves as if the whole pattern was inside a capture.
2571 </p>
2572
2573 <p>
2574 If the value returned by the table query or by the function call
2575 is not <b>nil</b>,
2576 then it is used as the replacement string;
2577 otherwise, if it is <b>nil</b>,
2578 then there is no replacement
2579 (that is, the original match is kept in the string).
2580 </p>
2581
2582 <p>
2583 Here are some examples:
2584 </p>
2585 <pre>
2586 x = String.gsub("hello world", [[(\w+)]], "$1 $1")
2587 --&gt; x="hello hello world world"
2588
2589 x = String.gsub("hello world", [[\w+]], "$0 $0", 1)
2590 --&gt; x="hello hello world"
2591
2592 x = String.gsub("hello world from Luan", [[(\w+)\s*(\w+)]], "$2 $1")
2593 --&gt; x="world hello Luan from"
2594
2595 x = String.gsub("4+5 = $return 4+5$", [[\$(.*?)\$]], function (s)
2596 return load(s)()
2597 end)
2598 --&gt; x="4+5 = 9"
2599
2600 local t = {name="lua", version="5.3"}
2601 x = String.gsub("$name-$version.tar.gz", [[\$(\w+)]], t)
2602 --&gt; x="lua-5.3.tar.gz"
2603 </pre>
2604 <%
2605 end
2606 }
2607 ["String.lower"] = { 2488 ["String.lower"] = {
2608 title = "<code>String.lower (s)</code>" 2489 title = "<code>String.lower (s)</code>"
2609 content = function() 2490 content = function()
2610 %> 2491 %>
2611 <p> 2492 <p>
2612 Receives a string and returns a copy of this string with all 2493 Receives a string and returns a copy of this string with all
2613 uppercase letters changed to lowercase. 2494 uppercase letters changed to lowercase.
2614 All other characters are left unchanged. 2495 All other characters are left unchanged.
2615 </p> 2496 </p>
2616 <%
2617 end
2618 }
2619 ["String.match"] = {
2620 title = "<code>String.match (s, pattern [, init])</code>"
2621 content = function()
2622 %>
2623 <p>
2624 Looks for the first <em>match</em> of
2625 <code>pattern</code> (see <a href="http://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html">Pattern</a>) in the string <code>s</code>.
2626 If it finds one, then <code>match</code> returns
2627 the captures from the pattern;
2628 otherwise it returns <b>nil</b>.
2629 If <code>pattern</code> specifies no captures,
2630 then the whole match is returned.
2631 A third, optional numerical argument <code>init</code> specifies
2632 where to start the search;
2633 its default value is&nbsp;1 and can be negative.
2634 </p>
2635 <%
2636 end
2637 }
2638 ["String.matches"] = {
2639 title = "<code>String.matches (s, pattern)</code>"
2640 content = function()
2641 %>
2642 <p>
2643 Returns a boolean indicating whether the <code>pattern</code> can be found in string <code>s</code>.
2644 This function is equivalent to
2645 </p>
2646 <pre>
2647 return String.match(s,pattern) ~= nil
2648 </pre>
2649 <% 2497 <%
2650 end 2498 end
2651 } 2499 }
2652 ["String.regex"] = { 2500 ["String.regex"] = {
2653 title = "<code>String.regex (s)</code>" 2501 title = "<code>String.regex (s)</code>"