v1.0.4 of glob released. glob is a file and directory globbing library that supports both checking whether a path matches a glob and listing all entities that match a glob. A glob is a pattern designed specifically to match files and directories. Most shells support globs natively. Usage To construct a glob, just use new Glob(). As with RegExps, its a good idea to keep around a glob if youll be using it more than once so that it doesnt have to be compiled over and over. You can check whether a path matches the glob using Glob.matches(): import package:glob/glob.dart; final dartFile = new Glob(**.dart); // Print all command-line arguments that are Dart files. void main(List arguments) { for (var argument in arguments) { if (dartFile.matches(argument)) print(argument); } } You can also list all files that match a glob using Glob.list() or Glob.listSync(): import package:glob/glob.dart; final dartFile = new Glob(**.dart); // Recursively list all Dart files in the current directory. void main(List arguments) { for (var entity in dartFile.listSync()) { print(entity.path); } } Syntax The glob syntax hews closely to the widely-known Bash glob syntax, with a few exceptions that are outlined below. In order to be as cross-platform and as close to the Bash syntax as possible, all globs use POSIX path syntax, including using / as a directory separator regardless of which platform theyre on. This is true even for Windows roots; for example, a glob matching all files in the C drive would be C:/*. Match any characters in a filename: * The * character matches zero or more of any character other than /. This means that it can be used to match all files in a given directory that match a pattern without also matching files in a subdirectory. For example, lib/*.dart will match lib/glob.dart but not lib/src/utils.dart. Match any characters across directories: ** ** is like *, but matches / as well. Its useful for matching files or listing directories recursively. For example, lib/**.dart will match both lib/glob.dart and lib/src/utils.dart. If ** appears at the beginning of a glob, it wont match absolute paths or paths beginning with ../. For example, **.dart wont match /foo.dart, although /**.dart will. This is to ensure that listing a bunch of paths and checking whether they match a glob produces the same results as listing that glob. In the previous example, /foo.dart wouldnt be listed for **.dart, so it shouldnt be matched by it either. This is an extension to Bash glob syntax thats widely supported by other glob implementations. Match any single character: ? The ? character matches a single character other than /. Unlike *, it wont match any more or fewer than one character. For example, test?.dart will match test1.dart but not test10.dart or test.dart. Match a range of characters: [...] The [...] construction matches one of several characters. It can contain individual characters, such as [abc], in which case it will match any of those characters; it can contain ranges, such as [a-zA-Z], in which case it will match any characters that fall within the range; or it can contain a mix of both. It will only ever match a single character. For example, test[a-zA-Z_].dart will match testx.dart, testA.dart, and test_.dart, but not test-.dart. If it starts with ^ or !, the construction will instead match all characters not mentioned. For example, test[^a-z].dart will match test1.dart but not testa.dart. This construction never matches /. Match one of several possibilities: {...,...} The {...,...} construction matches one of several options, each of which is a glob itself. For example, lib/{*.dart,src/*} matches lib/glob.dart and lib/src/data.txt. It can contain any number of options greater than one, and can even contain nested options. This is an extension to Bash glob syntax, although it is supported by other layers of Bash and is often used in conjunction with globs. Escaping a character: \ The \ character can be used in any context to escape a character that would otherwise be semantically meaningful. For example, \*.dart matches *.dart but not test.dart. Syntax errors Because theyre used as part of the shell, almost all strings are valid Bash globs. This implementation is more picky, and performs some validation to ensure that globs are meaningful. For instance, unclosed { and [ are disallowed. Reserved syntax: (...) Parentheses are reserved in case this package adds support for Bash extended globbing in the future. For the time being, using them will throw an error unless theyre escaped. #dartlang
Posted on: Thu, 22 Jan 2015 00:48:01 +0000
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