IDE regular expressions: what changed

Revision 1 to 2. Removed lines have a minus sign; added lines have a plus sign.

Old	New		Line
1	1		## Normal regular expression
2	2
3	3		Metacharacters:
4	4
5		-	~~` \ Quote the next metacharacter`\~~
6		-	~~` ^ Match the beginning of the line`\~~
7		-	~~` . Match any character (except newline). Example: 'a.c' matches 'abc', 'aBC', 'axc', 'a3c', 'a$c', etc.`\~~
8		-	~~` $ Match the end of the line (or before newline at the end)`\~~
9		-	~~` \| Alternation`\~~
10		-	~~` () Grouping. For example: (abc)+ matches 'abc' or 'abcabc' or 'abcabcabc' etc.`\~~
11		-	~~` [] Character class. For example [abc], [a-z], [a-zA-Z0-9_]`\~~
12		-	~~` [^] Reversed character class. For example [^a-z]`~~
	5	+	``` pascal
	6	+	\ Quote the next metacharacter
	7	+	^ Match the beginning of the line
	8	+	. Match any character (except newline). Example: 'a.c' matches 'abc', 'aBC', 'axc', 'a3c', 'a$c', etc.
	9	+	$ Match the end of the line (or before newline at the end)
	10	+	\| Alternation
	11	+	() Grouping. For example: (abc)+ matches 'abc' or 'abcabc' or 'abcabcabc' etc.
	12	+	[] Character class. For example [abc], [a-z], [a-zA-Z0-9_]
	13	+	[^] Reversed character class. For example [^a-z]
	14	+	```
13	15
14	16		Quantifiers:
15	17
16		-	~~` * Match 0 or more times`\~~
17		-	~~` + Match 1 or more times`\~~
18		-	~~` ? Match 1 or 0 times`\~~
19		-	~~` {n} Match exactly n times`\~~
20		-	~~` {n,} Match at least n times`\~~
21		-	~~` {n,m} Match at least n but not more than m times`~~
	18	+	```text
	19	+	* Match 0 or more times
	20	+	+ Match 1 or more times
	21	+	? Match 1 or 0 times
	22	+	{n} Match exactly n times
	23	+	{n,} Match at least n times
	24	+	{n,m} Match at least n but not more than m times
	25	+	```
22	26
23	27		Curly brackets in any other context is treated as a regular character. The \`\`*is equivalent to {0,}, the \`\`+ to {1,} and the \`\`?'' to {0,1}.
24	28
25	29		By default, a quantifier is greedy, that means, it will match as many times as possible. To match the minimum number of times possible, append a \`\`?''.
26	30
27		-	~~` *? Match 0 or more times`\~~
28		-	~~` +? Match 1 or more times`\~~
29		-	~~` ?? Match 0 or 1 time`\~~
30		-	~~` {n}? Match exactly n times`\~~
31		-	~~` {n,}? Match at least n times`\~~
32		-	~~` {n,m}? Match at least n but not more than m times`~~
	31	+	```text
	32	+	*? Match 0 or more times
	33	+	+? Match 1 or more times
	34	+	?? Match 0 or 1 time
	35	+	{n}? Match exactly n times
	36	+	{n,}? Match at least n times
	37	+	{n,m}? Match at least n but not more than m times
	38	+	```
33	39
34	40		## Simple Syntax
35	41
36	42		Some IDE dialogs provide a checkbox to choose between simple syntax and regular expressions. The simple syntax is often shorter for common file name filters.
37	43
38	44		Technically it does this:
39	45
40	46		The following characters are replaced with
41	47		. -> \.
42	48		* -> .*
43	49		? -> .
44	50		, -> \|
45	51		; -> \|
46	52
47	53		Finally enclose by ^( )$
48	54
49	55		### Examples for simple syntax
50	56
51	57		- *.pas - matches all file names ending with .pas, like Unit1.pas or Some.txt.pas. Default is to match case sensitive. So it does not fit unit1.PAS.
52	58		- .pas;.pp;*p - matches all files like unit1.pas, 678.pp or %.p
53	59		- unit.pas - matches all files beginning with unit* and ending with .pas like unit1.pas and unit.pas.
54	60		- unit?.pas - matches all files beginning with unit, ending with .pas and exactly one like arbitrary character in between like unit1.pas and unit2.pas.
55	61
56	62		## Quoted symbols
57	63
58	64		The backslash '\\' can be used to treat special characters like '.' as normal character or to get some special ranges.
59	65
60	66		\. matches a point '.'
61	67		\d matches a number character '0'..'9'
62	68		\D matches a non number character
63	69		\s matches a space character ' ',#9,#10,#12,#13
64	70		\S matches a non space character
65	71		\w matches a word character 'a'..'z','A'..'Z','0'..'9','_'
66	72		\W matches a non word character
67	73		\b word boundary
68	74		\B not word boundary
69	75		\A begin of line
70	76		\Z end of line
71	77
72	78		## Search and Replace with regular expressions
73	79
74	80		The find dialogs support regular expressions for finding and replacing. Each found pattern grouped in round brackets can be used by a \$1, ..., \$9 variable
75	81
76	82		Example 1:
77	83
78	84		- Find expression: a(.*)c
79	85		- Replace expression: A\$1C
80	86		- Text: 'abc aLazc'
81	87
82	88		The \$1 will be replaced with the found text, that matches the first bracket.
83	89
84	90		- Result: 'AbC ALazC'
85	91
86	92		Example 2:
87	93
88	94		- Find expression: T(prefix)(\w+)
89	95		- Replace expression: T\$2Suffix
90	96		- Text: replaced from 'TprefixClass' to 'TClassSuffix'
91	97
92	98		You can also use the following special chars in the replace term
93	99
94	100		\n
95	101		Inserts a Linebreak
96	102
97	103		\l \u
98	104		Lower or Uppercases the next Char. Use this in front of \$n. \u\$1 Will insert the match from the first brackets, but with its first char made uppercase
99	105
100	106		\L \U
101	107		Lower or Uppercase the full text of the next \$n. The \$n must follow immediately
102	108
103	109		---
104	110		From the Free Pascal wiki, page "IDE regular expressions", as it stood on 2022-02-05 after a change by Trev, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).

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