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<ol class="chapter"><li class="chapter-item affix "><a href="../../index.html">Andrew's Blog</a></li><li class="chapter-item "><a href="../../posts/linux/linux.html"><strong aria-hidden="true">1.</strong> linux</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/linux/install_linux.html"><strong aria-hidden="true">1.1.</strong> install linux</a></li><li class="chapter-item "><a href="../../posts/linux/bash_profile.html"><strong aria-hidden="true">1.2.</strong> bash profile</a></li><li class="chapter-item "><a href="../../posts/linux/command_list.html"><strong aria-hidden="true">1.3.</strong> command list</a></li><li class="chapter-item "><a href="../../posts/linux/git_guide.html"><strong aria-hidden="true">1.4.</strong> git guide</a></li><li class="chapter-item "><a href="../../posts/linux/tar.html"><strong aria-hidden="true">1.5.</strong> tar</a></li><li class="chapter-item "><a href="../../posts/linux/run_x86_elf_in_x64_setup.html"><strong aria-hidden="true">1.6.</strong> run x86 elf in x64 setup</a></li></ol></li><li class="chapter-item "><a href="../../posts/mac/mac.html"><strong aria-hidden="true">2.</strong> mac</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/mac/macos_profiles.html"><strong aria-hidden="true">2.1.</strong> macos profiles</a></li></ol></li><li class="chapter-item expanded "><a href="../../posts/swift/swift.html"><strong aria-hidden="true">3.</strong> swift</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/swift/learn_swift.html"><strong aria-hidden="true">3.1.</strong> learn swift basics</a></li><li class="chapter-item "><a href="../../posts/swift/swift_extensions.html"><strong aria-hidden="true">3.2.</strong> Swift extensions</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_extension.html"><strong aria-hidden="true">3.3.</strong> SwiftUI extensions</a></li><li class="chapter-item "><a href="../../posts/swift/install_swift.html"><strong aria-hidden="true">3.4.</strong> install swift</a></li><li class="chapter-item "><a href="../../posts/swift/task_planner.html"><strong aria-hidden="true">3.5.</strong> implment task panner app with SwiftUI</a></li><li class="chapter-item "><a href="../../posts/swift/swift_cheat_sheet.html"><strong aria-hidden="true">3.6.</strong> Swift Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/swift/yinci_url.html"><strong aria-hidden="true">3.7.</strong> Personal privacy protocol</a></li><li class="chapter-item expanded "><a href="../../posts/swift/swift_regular_exressions.html" class="active"><strong aria-hidden="true">3.8.</strong> Swift regular exressions</a></li><li class="chapter-item "><a href="../../posts/ios/how_to_create_beautiful_ios_charts_in_swift.html"><strong aria-hidden="true">3.9.</strong> How to Create Beautiful iOS Charts in鑱絊wift</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_source_code.html"><strong aria-hidden="true">3.10.</strong> SwiftUI source code</a></li><li class="chapter-item "><a href="../../posts/swift/use_swift_fetch_iciba_api.html"><strong aria-hidden="true">3.11.</strong> use swift fetch iciba API</a></li></ol></li><li class="chapter-item "><a href="../../posts/ios/ios.html"><strong aria-hidden="true">4.</strong> ios</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ios/cocaposd_setup_and_install_for_ios_project.html"><strong aria-hidden="true">4.1.</strong> cocaposd setup and install for ios project</a></li><li class="chapter-item "><a href="../../posts/ios/swiftui_show_gif_image.html"><strong aria-hidden="true">4.2.</strong> SwiftUI show gif image</a></li><li class="chapter-item "><a href="../../posts/ios/implement_task_planner_app.html"><strong aria-hidden="true">4.3.</strong> implement Task planner App</a></li></ol></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c.html"><strong aria-hidden="true">5.</strong> objective_c</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/objective_c/objective_c_cheat_sheet.html"><strong aria-hidden="true">5.1.</strong> Objective-C Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c_for_absolute_beginners_read_note.html"><strong aria-hidden="true">5.2.</strong> Objective-C Note</a></li></ol></li><li class="chapter-item "><a href="../../posts/dart/dart.html"><strong aria-hidden="true">6.</strong> dart</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/dart/flutter.html"><strong aria-hidden="true">6.1.</strong> Flutter Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/dart/dart_cheat_sheet.html"><strong aria-hidden="true">6.2.</strong> Dart Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/flutter/flutter_dev_test.html"><strong aria-hidden="true">6.3.</strong> Flutter dev test</a></li></ol></li><li class="chapter-item "><a href="../../posts/rust/rust.html"><strong aria-hidden="true">7.</strong> rust</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/rust/offline_use_rust.html"><strong aria-hidden="true">7.1.</strong> Offline use rust</a></li><li class="chapter-item "><a href="../../posts/rust/rust_grammer.html"><strong aria-hidden="true">7.2.</strong> rust grammar</a></li><li class="chapter-item "><a href="../../posts/rust/pase_string_and_decimal_conversion.html"><strong aria-hidden="true">7.3.</strong> pase string and decimal conversion</a></li><li class="chapter-item "><a href="../../posts/rust/parse_types.html"><strong aria-hidden="true">7.4.</strong> rust types</a></li><li class="chapter-item "><a href="../../posts/rust/rust_life_cycle.html"><strong aria-hidden="true">7.5.</strong> Rust life cycle</a></li><li class="chapter-item "><a href="../../posts/rust/rust_generic.html"><strong aria-hidden="true">7.6.</strong> rust generics</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implment_matrix.html"><strong aria-hidden="true">7.7.</strong> Rust implement matrix</a></li><li class="chapter-item "><a href="../../posts/rust/rust_sort.html"><strong aria-hidden="true">7.8.</strong> Rust implement sort algorithms</a></li><li class="chapter-item "><a href="../../posts/rust/implement_aes_encryption.html"><strong aria-hidden="true">7.9.</strong> Rust implement AEC encryption and decryption</a></li><li class="chapter-item "><a href="../../posts/rust/implement_trie_data_structure.html"><strong aria-hidden="true">7.10.</strong> implement trie data structure</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_tree.html"><strong aria-hidden="true">7.11.</strong> implement tree data_structure</a></li><li class="chapter-item "><a href="../../posts/rust/list_dir.html"><strong aria-hidden="true">7.12.</strong> list dir</a></li><li class="chapter-item "><a href="../../posts/rust/fast_way_to_implment_object_trait.html"><strong aria-hidden="true">7.13.</strong> fast way to implment object trait</a></li><li class="chapter-item "><a href="../../posts/rust/compress_rust_binary_size.html"><strong aria-hidden="true">7.14.</strong> compress rust binary size</a></li><li class="chapter-item "><a href="../../posts/rust/implment_file_upload_backend.html"><strong aria-hidden="true">7.15.</strong> impliment file upload</a></li><li class="chapter-item "><a href="../../posts/rust/this_is_add_post_cli_implementation_in_rust.html"><strong aria-hidden="true">7.16.</strong> this is add_post cli implementation in rust</a></li><li class="chapter-item "><a href="../../posts/rust/use_rust_implment_a_copyclipbord_cli.html"><strong aria-hidden="true">7.17.</strong> Use rust implment a copyclipbord CLI</a></li><li class="chapter-item "><a href="../../posts/rust/sqlite_database_add_delete_update_show_in_rust.html"><strong aria-hidden="true">7.18.</strong> sqlite database add delete update show in rust</a></li><li class="chapter-item "><a href="../../posts/rust/implementing_tokio_joinhandle_for_wasm.html"><strong aria-hidden="true">7.19.</strong> Implementing tokio JoinHandle for wasm</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_a_crate_for_encode_and_decode_brainfuck_and_ook.html"><strong aria-hidden="true">7.20.</strong> rust implement a crate for encode and decode brainfuck and ook</a></li><li class="chapter-item "><a href="../../posts/rust/slint_builtin_elements.html"><strong aria-hidden="true">7.21.</strong> Slint Builtin Elements</a></li><li class="chapter-item "><a href="../../posts/rust/corporate_network_install_rust_on_windows.html"><strong aria-hidden="true">7.22.</strong> Corporate network install Rust on windows</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_file_how_to_judge_static_link_or_dynamic_link_in_macos.html"><strong aria-hidden="true">7.23.</strong> rust binary file how to judge static link or dynamic link in Macos</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_include_dir_and_get_contents.html"><strong aria-hidden="true">7.24.</strong> rust binary include dir and get contents</a></li><li class="chapter-item "><a href="../../posts/rust/rust_logger_non-block.html"><strong aria-hidden="true">7.25.</strong> rust logger non-block</a></li><li class="chapter-item "><a href="../../posts/rust/rust_connect_sql_server_database.html"><strong aria-hidden="true">7.26.</strong> rust connect sql server database</a></li><li class="chapter-item "><a href="../../posts/rust/rust_websocket_implment.html"><strong aria-hidden="true">7.27.</strong> rust websocket implment</a></li></ol></li><li class="chapter-item "><a href="../../posts/java/java.html"><strong aria-hidden="true">8.</strong> java</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/java/java_grammar.html"><strong aria-hidden="true">8.1.</strong> java grammar and codewar</a></li><li class="chapter-item "><a href="../../posts/java/run_jar.html"><strong aria-hidden="true">8.2.</strong> java run .jar</a></li><li class="chapter-item "><a href="../../posts/java/java_pomxml_add_defaultgoal_to_build.html"><strong aria-hidden="true">8.3.</strong> Java pomxml add defaultGoal to build</a></li><li class="chapter-item "><a href="../../posts/java/java_set_mvn_mirror.html"><strong aria-hidden="true">8.4.</strong> Java set mvn mirror</a></li></ol></li><li class="chapter-item "><a href="../../posts/python/python.html"><strong aria-hidden="true">9.</strong> python</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/python/convert_pesn.html"><strong aria-hidden="true">9.1.</strong> convert pesn</a></li><li class="chapter-item "><a href="../../posts/python/find_remove_dir.html"><strong aria-hidden="true">9.2.</strong> find and remove dir</a></li><li class="chapter-item "><a href="../../posts/python/timing_message.html"><strong aria-hidden="true">9.3.</strong> wechat send message</a></li><li class="chapter-item "><a href="../../posts/python/use_python_openpyxl_package_read_and_edit_excel_files.html"><strong aria-hidden="true">9.4.</strong> Use python openpyxl package read and edit excel files</a></li></ol></li><li class="chapter-item "><a href="../../posts/go/go.html"><strong aria-hidden="true">10.</strong> go</a></li><li class="chapter-item "><a href="../../posts/js/js.html"><strong aria-hidden="true">11.</strong> js</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/js/js_tutorial.html"><strong aria-hidden="true">11.1.</strong> js tutorial</a></li><li class="chapter-item "><a href="../../posts/js/js_tutorial_map.html"><strong aria-hidden="true">11.2.</strong> ja map</a></li><li class="chapter-item "><a href="../../posts/js/js_tutorial_math.html"><strong aria-hidden="true">11.3.</strong> js math</a></li><li class="chapter-item "><a href="../../posts/js/js_tutorial_object.html"><strong aria-hidden="true">11.4.</strong> js object</a></li><li class="chapter-item "><a href="../../posts/js/js_tutorial_set.html"><strong aria-hidden="true">11.5.</strong> js set</a></li><li class="chapter-item "><a href="../../posts/js/single_thread_and_asynchronous.html"><strong aria-hidden="true">11.6.</strong> single thread and asynchronous</a></li><li class="chapter-item "><a href="../../posts/js/this.html"><strong aria-hidden="true">11.7.</strong> js this</a></li><li class="chapter-item "><a href="../../posts/js/js_implment_aes.html"><strong aria-hidden="true">11.8.</strong> js implment aes</a></li><li class="chapter-item "><a href="../../posts/js/getting_started_with_ajax.html"><strong aria-hidden="true">11.9.</strong> getting started with ajax</a></li><li class="chapter-item "><a href="../../posts/js/BinarySearchTree.html"><strong aria-hidden="true">11.10.</strong> binary search tree</a></li><li class="chapter-item "><a href="../../posts/js/goole_zx.html"><strong aria-hidden="true">11.11.</strong> goole zx</a></li><li class="chapter-item "><a href="../../posts/js/es6.html"><strong aria-hidden="true">11.12.</strong> es6</a></li></ol></li><li class="chapter-item "><a href="../../posts/ruby/ruby.html"><strong aria-hidden="true">12.</strong> ruby</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ruby/rails_setup_env.html"><strong aria-hidden="true">12.1.</strong> ruby on rails setup environment</a></li><li class="chapter-item "><a href="../../posts/ruby/learn_ruby.html"><strong aria-hidden="true">12.2.</strong> learn ruby</a></li><li class="chapter-item "><a href="../../posts/ruby/ruby_note.html"><strong aria-hidden="true">12.3.</strong> Ruby Note</a></li><li class="chapter-item "><a href="../../posts/ruby/setup_ruby_for_ctf.html"><strong aria-hidden="true">12.4.</strong> Setup ruby for CTF</a></li></ol></li><li class="chapter-item "><a href="../../posts/react/react.html"><strong aria-hidden="true">13.</strong> react</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/react/react_life_cycle.html"><strong aria-hidden="true">13.1.</strong> react life cycle</a></li><li class="chapter-item "><a href="../../posts/react/react_router.html"><strong aria-hidden="true">13.2.</strong> react router</a></li><li class="chapter-item "><a href="../../posts/react/react_this.html"><strong aria-hidden="true">13.3.</strong> react this</a></li><li class="chapter-item "><a href="../../posts/react/react_interviw.html"><strong aria-hidden="true">13.4.</strong> react interview</a></li><li class="chapter-item "><a href="../../posts/react/important_react_interview.html"><strong aria-hidden="true">13.5.</strong> important react interview</a></li><li class="chapter-item "><a href="../../posts/react/react_quick_reference.html"><strong aria-hidden="true">13.6.</strong> react quick reference</a></li><li class="chapter-item "><a href="../../posts/react/redux_quick_reference.html"><strong aria-hidden="true">13.7.</strong> redux quick reference</a></li></ol></li><li class="chapter-item "><a href="../../posts/vue/vue.html"><strong aria-hidden="true">14.</strong> vue</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/vue/vue_ajax.html"><strong aria-hidden="true">14.1.</strong> vue ajax</a></li></ol></li><li class="chapter-item "><a href="../../posts/angular/angular.html"><strong aria-hidden="true">15.</strong> angular</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/angular/controller_communication.html"><strong aria-hidden="true">15.1.</strong> controller communication</a></li><li class="chapter-item "><a href="../../posts/angular/creating_custom_directives.html"><strong aria-hidden="true">15.2.</strong> creating custom directives</a></li><li class="chapter-item "><a href="../../posts/angular/directive_notes.html"><strong aria-hidden="true">15.3.</strong> directive notes</a></li><li class="chapter-item "><a href="../../posts/angular/directive_communication.html"><strong aria-hidden="true">15.4.</strong> directive communication</a></li><li class="chapter-item "><a href="../../posts/angular/post_params.html"><strong aria-hidden="true">15.5.</strong> post params</a></li><li class="chapter-item "><a href="../../posts/angular/read_json_angular.html"><strong aria-hidden="true">15.6.</strong> read json angular</a></li><li class="chapter-item "><a href="../../posts/angular/same_route_reload.html"><strong aria-hidden="true">15.7.</strong> same route reload</a></li></ol></li><li class="chapter-item "><a href="../../posts/css/css.html"><strong aria-hidden="true">16.</strong> css</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/css/use_css_media.html"><strong aria-hidden="true">16.1.</strong> use css media</a></li></ol></li><li class="chapter-item "><a href="../../posts/php/php.html"><strong aria-hidden="true">17.</strong> php</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/php/for_php_string_implment_some_extemtion_functions.html"><strong aria-hidden="true">17.1.</strong> for php string implment some extemtion functions</a></li><li class="chapter-item "><a href="../../posts/php/php_cheatsheet.html"><strong aria-hidden="true">17.2.</strong> PHP cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/leetcode/leetcode.html"><strong aria-hidden="true">18.</strong> leetcode</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/leetcode/rust_leetcode.html"><strong aria-hidden="true">18.1.</strong> rust leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_codewar.html"><strong aria-hidden="true">18.2.</strong> rust codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/swift_codewar.html"><strong aria-hidden="true">18.3.</strong> swift codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/js_leetcode.html"><strong aria-hidden="true">18.4.</strong> js leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/java_leetcode.html"><strong aria-hidden="true">18.5.</strong> java leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_huawei.html"><strong aria-hidden="true">18.6.</strong> huawei test</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_utils.html"><strong aria-hidden="true">18.7.</strong> rust common functions</a></li><li class="chapter-item "><a href="../../posts/leetcode/olympiad_training.html"><strong aria-hidden="true">18.8.</strong> Computer olympiad training</a></li></ol></li><li class="chapter-item "><a href="../../posts/ctf/CTF.html"><strong aria-hidden="true">19.</strong> ctf</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ctf/CTF_Note.html"><strong aria-hidden="true">19.1.</strong> CTF Note</a></li><li class="chapter-item "><a href="../../posts/ctf/0.1_Web.html"><strong aria-hidden="true">19.2.</strong> Web</a></li><li class="chapter-item "><a href="../../posts/ctf/4.1_Misc.html"><strong aria-hidden="true">19.3.</strong> Misc</a></li><li class="chapter-item "><a href="../../posts/ctf/3.2_PWN_note.html"><strong aria-hidden="true">19.4.</strong> PWN</a></li><li class="chapter-item "><a href="../../posts/ctf/3.1_Crypto.html"><strong aria-hidden="true">19.5.</strong> Crypto</a></li><li class="chapter-item "><a href="../../posts/ctf/3.4_RSA_note.html"><strong aria-hidden="true">19.6.</strong> Rsa attack</a></li><li class="chapter-item "><a href="../../posts/ctf/3.5_Base64.html"><strong aria-hidden="true">19.7.</strong> Base64</a></li><li class="chapter-item "><a href="../../posts/ctf/0.0_SQL Injection Cheatsheet.html"><strong aria-hidden="true">19.8.</strong> SQL Injection Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/ctf/1.1_SQL_injection.html"><strong aria-hidden="true">19.9.</strong> SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.2_SQL_injection_UNION_attacks.html"><strong aria-hidden="true">19.10.</strong> SQL Injection UNION attacks</a></li><li class="chapter-item "><a href="../../posts/ctf/1.3_Blind SQL injection.html"><strong aria-hidden="true">19.11.</strong> Blind SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.4_Code Injection.html"><strong aria-hidden="true">19.12.</strong> Code Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.5_SSRF.html"><strong aria-hidden="true">19.13.</strong> SSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.6_OS command injection.html"><strong aria-hidden="true">19.14.</strong> OS command injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.7_Local file inclusion.html"><strong aria-hidden="true">19.15.</strong> Local file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.8_Remote file inclusion.html"><strong aria-hidden="true">19.16.</strong> Remote file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.9_CSRFm.html"><strong aria-hidden="true">19.17.</strong> CSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.10_NoSQL injection.html"><strong aria-hidden="true">19.18.</strong> NoSQL injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.11_JSON injection.html"><strong aria-hidden="true">19.19.</strong> JSON injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.12_CTF_Web_SQL_Note.html"><strong aria-hidden="true">19.20.</strong> CTF Web SQL Note</a></li><li class="chapter-item "><a href="../../posts/ctf/2.1_XXE.html"><strong aria-hidden="true">19.21.</strong> XXE</a></li><li class="chapter-item "><a href="../../posts/ctf/2.2_XSS.html"><strong aria-hidden="true">19.22.</strong> XSS</a></li><li class="chapter-item "><a href="../../posts/ctf/2.3_Upload File.html"><strong aria-hidden="true">19.23.</strong> Upload File</a></li><li class="chapter-item "><a href="../../posts/ctf/2.4_serialize_unserialize.html"><strong aria-hidden="true">19.24.</strong> serialize unserialize</a></li><li class="chapter-item "><a href="../../posts/ctf/2.5_Race condition.html"><strong aria-hidden="true">19.25.</strong> Race condition</a></li><li class="chapter-item "><a href="../../posts/ctf/3.2_PWN_note.html"><strong aria-hidden="true">19.26.</strong> PWN_note</a></li><li class="chapter-item "><a href="../../posts/ctf/3.3_pwn HCTF2016 brop.html"><strong aria-hidden="true">19.27.</strong> pwn HCTF2016 brop</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_patch_defense_skill.html"><strong aria-hidden="true">19.28.</strong> PWN Patch defense skill</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_stack_overflow.html"><strong aria-hidden="true">19.29.</strong> PWN stack overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_heap_overflow.html"><strong aria-hidden="true">19.30.</strong> PWN heap overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_format_string_vulnerability.html"><strong aria-hidden="true">19.31.</strong> PWN Format String Vulnerability</a></li><li class="chapter-item "><a href="../../posts/ctf/kali_linux_tutorials.html"><strong aria-hidden="true">19.32.</strong> Kali linux tutorials</a></li><li class="chapter-item "><a href="../../posts/ctf/google_dorks_2023_lists.html"><strong aria-hidden="true">19.33.</strong> Google Dorks 2023 Lists</a></li><li class="chapter-item "><a href="../../posts/ctf/dvwa_writeup.html"><strong aria-hidden="true">19.34.</strong> DVWA WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/bwapp_writeup.html"><strong aria-hidden="true">19.35.</strong> bWAPP WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/sqlilabs_writeup.html"><strong aria-hidden="true">19.36.</strong> sqlilabs WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/ctf_train_at_hangzhou.html"><strong aria-hidden="true">19.37.</strong> ctf train at hangzhou</a></li><li class="chapter-item "><a href="../../posts/ctf/ctf_common_mindmap_list.html"><strong aria-hidden="true">19.38.</strong> ctf common mindmap list</a></li><li class="chapter-item "><a href="../../posts/ctf/error_based_sql_injection.html"><strong aria-hidden="true">19.39.</strong> Error Based SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/urlfinder_tutorial.html"><strong aria-hidden="true">19.40.</strong> URLFinder Tutorial</a></li><li class="chapter-item "><a href="../../posts/ctf/observer_ward_tutorial.html"><strong aria-hidden="true">19.41.</strong> observer_ward Tutorial</a></li><li class="chapter-item "><a href="../../posts/ctf/mysql_udf_.html"><strong aria-hidden="true">19.42.</strong> MySQL UDF 提权</a></li><li class="chapter-item "><a href="../../posts/ctf/nuclei__tutorial.html"><strong aria-hidden="true">19.43.</strong> Nuclei Tutorial</a></li><li class="chapter-item "><a href="../../posts/ctf/2024_ctf_solution_thinking.html"><strong aria-hidden="true">19.44.</strong> 2024 ctf solution thinking</a></li><li class="chapter-item "><a href="../../posts/ctf/man_che_si_te_bian_ma.html"><strong aria-hidden="true">19.45.</strong> 曼彻斯特编码</a></li></ol></li></ol>
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<h1 id="swift-regular-exressions"><a class="header" href="#swift-regular-exressions">Swift regular exressions</a></h1>
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<p style="display:flex;
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align-items: center;
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justify-content: end;
|
||
">Pub Date: 2023-07-25</p>
|
||
Swift 5.7 中引入了正则表达式的语法支持，整理一下相关的一些话题、方法和示例，以备今后自己能够速查。
|
||
## 总览
|
||
Swift 正则由标准库中的 `Regex` 类型驱动，需要 iOS 16.0 或 macOS 13.0，早期的 deploy 版本无法使用。
|
||
构建一个正则表达式的方式，分为传统的正则字面量构建，以及通过 Regex Builder DSL 的更加易读的方式。后者可以内嵌使用前者，以及其他一些已有的 parser，在可读性和功能上要强力很多。实践中，推荐**结合使用字面量和 Builder API 在简洁和易读之间获取平衡**。
|
||
## 常见字面量
|
||
和其他各语言正则表达式的字面量没有显著不同。
|
||
直接将字面量包裹在 `/.../` 中使用，Swift 将把类似的声明转换为 `Regex` 类型的实例：
|
||
```swift
|
||
let bitcoinAddress_v1 = /([13][a-km-zA-HJ-NP-Z0-9]{26,33})/
|
||
```
|
||
### 字符集
|
||
| 表达式 | 说明 | 示例 |
|
||
| ---------- | ------------------------------------- | --------------------------------------------- |
|
||
| `[aeiou]` | 匹配指定字符集 | On**e**V’s␣D**e**n␣**i**s␣**a**␣bl**o**g. |
|
||
| `[^aeiou]` | 排除字符集 | **On**e**V’s␣D**e**n␣**i**s␣**a**␣bl**o**g.** |
|
||
| `[A-Z]` | 匹配字符范围 | **O**ne**V**’s␣**D**en␣is␣a␣blog. |
|
||
| `.` | 除换行符以外的任意字符。等效于 `[^\n\r]` | **OneV’s␣Den␣is␣a␣blog.** |
|
||
| `\s` | 匹配空格字符 (包括 tab 和换行) | OneV’s**␣**Den**␣**is**␣**a**␣**blog. |
|
||
| `\S` | 匹配非空格字符 | **OneV’s**␣**Den**␣**is**␣**a**␣**blog.** |
|
||
| `[\s\S]` | 匹配空格和非空格，也即任意字符。等效于 `[^]` | **OneV’s␣Den␣is␣a␣blog.** |
|
||
| `\w` | 匹配字母数字下划线等低位 ASCII。等效于 `[A-Za-z0-9_]` | **OneV**‘**s**␣**Den**␣**is**␣**a**␣**blog**. |
|
||
| `\W` | 等效于 `[^A-Za-z0-9_]` | |
|
||
| `\d` | 匹配数字，等效于 `[0-9]` | +(**81**)**021**-**1234**-**5678** |
|
||
| `\D` | 非数字，等效于 `[^0-9]` | **+(** 81 **)** 021**-**1234**-**5678 |
|
||
### 数量
|
||
| 表达式 | 说明 | 示例 | 结果 |
|
||
| -------- | ------------------ | ------------- | --------------------------------------- |
|
||
| `+` | 匹配一个或多个 | `b\w+` | b **be** **bee** **beer** **beers** |
|
||
| `*` | 匹配零个或多个 | `b\w*` | **b** **be** **bee** **beer** **beers** |
|
||
| `{2,3}` | 匹配若干个 | `b\w{2,3}` | b be **bee** **beer** **beer**s |
|
||
| `?` | 匹配零个或一个 | `colou?r` | **color** **colour** |
|
||
| 数量 + `?` | 使前置数量进行惰性匹配 (尽可能少) | `b\w+?` | b **be** **be**e **be**er **be**ers |
|
||
| `\|` | 逻辑或，择一匹配 | `b(a\|e\|i)d` | **bad** bud bod **bed** **bid** |
|
||
### 锚点
|
||
| 表达式 | 说明 | 示例 | 结果 |
|
||
| ---- | --------------------- | ------ | ----------------------------------- |
|
||
| `^` | 匹配字符串开头 | `^\w+` | **she** sells seashells |
|
||
| `$` | 匹配字符串结尾 | `\w+$` | she sells **seashells** |
|
||
| `\b` | 匹配 `\w` 和非 `\w` 的边缘位置 | `s\b` | she sell**s** seashell**s** |
|
||
| `\B` | 匹配非边缘位置 | `s\B` | **s**he **s**ells **s**ea**s**hells |
|
||
### 捕获组
|
||
| 表达式 | 说明 | 示例 |
|
||
| ---------------- | ------------------------- | ------------------------- |
|
||
| `(OneV)+` | 捕获括号内的匹配，使其成组并出现在匹配结果中 | **OneV**’s Den is a blog. |
|
||
| `(?<name>OneV)+` | 命名捕获匹配，在结果中可使用名字对匹配结果进行引用 | |
|
||
| `(?:OneV)+` | 成组但不进行捕获，允许使用数量但不关心和捕获结果 | |
|
||
### Lookahead
|
||
| 表达式 | 说明 | 示例 |
|
||
| ---------- | ----------------------------------------- | ----------------------- |
|
||
| `\d(?=px)` | `?=` - Positive lookahead。预先检查，符合时再进行主体匹配 | 1pt **2**px 3em **4**px |
|
||
| `\d(?!px)` | `?!` - Negative lookahead。预先检查，不符合时进行主体匹配 | **1**pt 2px **3**em 4px
|
||
## Builder DSL
|
||
字面量表达式虽然简洁，但是对应复杂情境会难以理解，也不便于修改。使用 [`RegexBuilder` 框架](https://developer.apple.com/documentation/regexbuilder)提供的 DSL 来描述正则表达式是更具有表达性的方法。
|
||
比如，
|
||
```swift
|
||
let bitcoinAddress_v1 = /([13][a-km-zA-HJ-NP-Z0-9]{26,33})/
|
||
```
|
||
等效于：
|
||
```swift
|
||
<p>import RegexBuilder
|
||
let bitcoinAddress_v1 = Regex {
|
||
Capture {
|
||
One(.anyOf(“13”))
|
||
Repeat(26…33) {
|
||
CharacterClass(
|
||
(“a”…“k”),
|
||
(“m”…“z”),
|
||
(“A”…“H”),
|
||
(“J”…“N”),
|
||
(“P”…“Z”),
|
||
(“0”…“9”)
|
||
)
|
||
}
|
||
}
|
||
}</p>
|
||
<pre><code>`Regex.init(_:)` 接受一个 result builder 形式的闭包，你可以往闭包中塞入多个 `RegexComponent` 来构建完整的正则表达式。注意 `Regex` 类型本身也满足 `RegexComponent` 协议，所以你也可以直接把字面量传递给 `Regex` 初始化方法。
|
||
字面量所提供的特性，在 Regex Builder 中都有对应。除此之外，Swift Regex Builder 框架还提供了更易读的强类型描述。一些常见的对应 `RegexComponent` 如下：
|
||
### 字符集
|
||
字符集相关的 `RegexComponent` 基本被定义在 [`CharacterClass`](https://developer.apple.com/documentation/regexbuilder/characterclass) 中。
|
||
| 字面量表达式 | 等效的 `RegexComponent` |
|
||
| ---------- | ------------------------------------------------------- |
|
||
| `[aeiou]` | `.anyOf("aeiou")`。为了可读性，可以考虑加上量词 `One(.anyOf("aeiou"))` |
|
||
| `[^aeiou]` | `CharacterClass.anyOf("aeiou").inverted` |
|
||
| `[A-Z]` | `("A"..."Z")` |
|
||
| `.` | `.any` |
|
||
| `\s` | `.whitespace` |
|
||
| `\S` | `.whitespace.inverted` |
|
||
| `[\s\S]` | `CharacterClass(.whitespace, .whitespace.inverted)` |
|
||
| `\w` | `.word` |
|
||
| `\W` | `.word.inverted` |
|
||
| `\d` | `.digit` |
|
||
| `\D` | `.digit.inverted` |
|
||
### 数量
|
||
| 表达式 | 说明 | 示例 | 结果 |
|
||
| -------- | ------------------ | ------------- | --------------------------------------- |
|
||
| `+` | 匹配一个或多个 | `b\w+` | b **be** **bee** **beer** **beers** |
|
||
| `*` | 匹配零个或多个 | `b\w*` | **b** **be** **bee** **beer** **beers** |
|
||
| `{2,3}` | 匹配若干个 | `b\w{2,3}` | b be **bee** **beer** **beer**s |
|
||
| `?` | 匹配零个或一个 | `colou?r` | **color** **colour** |
|
||
| 数量 + `?` | 使前置数量进行惰性匹配 (尽可能少) | `b\w+?` | b **be** **be**e **be**er **be**ers |
|
||
| `\|` | 逻辑或，择一匹配 | `b(a\|e\|i)d` | **bad** bud bod **bed** **bid**
|
||
### 锚点
|
||
| 表达式 | 说明 | 示例 | 结果 |
|
||
| ---- | --------------------- | ------ | ----------------------------------- |
|
||
| `^` | 匹配字符串开头 | `^\w+` | **she** sells seashells |
|
||
| `$` | 匹配字符串结尾 | `\w+$` | she sells **seashells** |
|
||
| `\b` | 匹配 `\w` 和非 `\w` 的边缘位置 | `s\b` | she sell**s** seashell**s** |
|
||
| `\B` | 匹配非边缘位置 | `s\B` | **s**he **s**ells **s**ea**s**hells
|
||
此外：
|
||
- 对于多行匹配模式的情况 (如带有 `m` 的 `/^abc/m`)，此时 `^` 和 `$` 等效为 `.startOfLine`，`.endOfLine` 等。
|
||
- 对于 Unicode 支持，常用的还有 `.textSegmentBoundary (\y)` 等。
|
||
### 捕获
|
||
| 字面量表达式 | 等效的 `RegexComponent` |
|
||
| ---------------- | ----------------------------------------------------------------------------------- |
|
||
| `(OneV)+` | `OneOrMore { Capture { "OneV" } }` |
|
||
| `(?<name>OneV)+` | `let name = Reference(Substring.self)` `OneOrMore { Capture(as: name) { "OneV" } }` |
|
||
| `(?:OneV)+` | `OneOrMore { "OneV" }` |
|
||
Regex Builder 支持在 `Capture` 的过程中同时进行 mapping，把结果转换为其他形式的字符串甚至是其他类型的强类型值：
|
||
```swift
|
||
Regex {
|
||
TryCapture(as: kind) {
|
||
OneOrMore(.word)
|
||
} transform: {
|
||
Transaction.Kind($0)
|
||
} // 得到一个强类型 `Kind` 值
|
||
}
|
||
</code></pre>
|
||
<p>如果转换可能会失败并返回 <code>nil</code>，使用 <code>TryCapture</code>：失败时跳过匹配；如果转换一定会成功，使用普通的 <code>Capture</code>。</p>
|
||
<h3 id="lookahead"><a class="header" href="#lookahead">Lookahead</a></h3>
|
||
<div class="table-wrapper"><table><thead><tr><th>字面量表达式</th><th>等效的 <code>RegexComponent</code></th></tr></thead><tbody>
|
||
<tr><td><code>\d(?=px)</code></td><td><code>Regex { .digit ↵ Lookahead { "px" } }</code></td></tr>
|
||
<tr><td><code>\d(?!px)</code></td><td><code>Regex { .digit ↵ NegativeLookahead { "px" } }</code></td></tr>
|
||
</tbody></table>
|
||
</div>
|
||
<h2 id="常用-parser"><a class="header" href="#常用-parser">常用 Parser</a></h2>
|
||
<p>相对于字面量，使用 Regex Builder 的最大优势，在于可以嵌套使用已经存在的 Parser 进行匹配。凡是满足 <code>RegexComponent</code> 的值，都可以放到 <code>Regex</code> 表达式中。Foundation 中，部分 <code>ParseStrategy</code> 满足 <code>RegexComponent</code> 并提供相应方法来创建 <code>Regex</code> 中可用的 parser。iOS 16 中，默认可用 Parser 有：</p>
|
||
<div class="table-wrapper"><table><thead><tr><th>所属 Parser 类型</th><th>方法签名</th><th>可解析示例</th></tr></thead><tbody>
|
||
<tr><td><code>Date.ParseStrategy</code></td><td><code>date(_:locale:timeZone:calendar:)</code></td><td>Oct 21, 2015, 10/21/2015, etc</td></tr>
|
||
<tr><td><code>Date.ParseStrategy</code></td><td><code>date(format:locale:timeZone:calendar:twoDigitStartDate:)</code></td><td>05_04_22</td></tr>
|
||
<tr><td><code>Date.ParseStrategy</code></td><td><code>dateTime(date:time:locale:timeZone:calendar:)</code></td><td>10/17/2020, 9:54:29 PM</td></tr>
|
||
<tr><td><code>Date.ISO8601FormatStyle</code></td><td><code>iso8601(timeZone:...)</code></td><td>2021-06-21T211015</td></tr>
|
||
<tr><td><code>Date.ISO8601FormatStyle</code></td><td><code>iso8601Date(timeZone:dateSeparator:)</code></td><td>2015-11-14</td></tr>
|
||
<tr><td><code>Date.ISO8601FormatStyle</code></td><td><code>iso8601WithTimeZone(...)</code></td><td>2021-06-21T21:10:15+0800</td></tr>
|
||
<tr><td><code>Decimal.FormatStyle.Currency</code></td><td><code>localizedCurrency(code:locale:)</code></td><td>$52,249.98 -> <code>Decimal</code></td></tr>
|
||
<tr><td><code>Decimal.FormatStyle</code></td><td><code>localizedDecimal(locale:)</code></td><td>1.234, 1E5 -> <code>Decimal</code></td></tr>
|
||
<tr><td><code>FloatingPointFormatStyle<Double></code></td><td><code>localizedDouble(locale:)</code></td><td>1.234, 1E5 -> -> <code>Double</code></td></tr>
|
||
<tr><td><code>FlatingPointFormatStyle<Double>.Percent</code></td><td><code>localizedDoublePercentage(locale:)</code></td><td>15.4%, <code>-200%</code> -> <code>Double</code></td></tr>
|
||
<tr><td><code>IntegerFormatStyle<Int></code></td><td><code>localizedInteger(locale:)</code></td><td>199, 1.234 -> <code>Int</code></td></tr>
|
||
<tr><td><code>IntegerFormatStyle<Int>.Currency</code></td><td><code>localizedIntegerCurrency(code:locale:)</code></td><td>$52,249.98 -> <code>Int</code></td></tr>
|
||
<tr><td><code>IntegerFormatStyle<Int>.Percent</code></td><td><code>localizedIntegerPercentage(locale:)</code></td><td>15.4%, -200% -> <code>Int</code></td></tr>
|
||
</tbody></table>
|
||
</div>
|
||
<blockquote>
|
||
<p>关于 Foundation 中 <code>ParseStrategy</code> 的相关内容，可以参看肘子兄的<a href="https://www.fatbobman.com/posts/newFormatter/">这篇博客</a>，以及 WWDC 21 中<a href="https://developer.apple.com/videos/play/wwdc2021/10109/">相关的视频</a>。</p>
|
||
</blockquote>
|
||
<h3 id="自定义-parser-和-customconsumingregexcomponent"><a class="header" href="#自定义-parser-和-customconsumingregexcomponent">自定义 Parser 和 <code>CustomConsumingRegexComponent</code></a></h3>
|
||
<p>对于自己实现的或是第三方提供的 Parser，可以通过满足 <code>CustomConsumingRegexComponent</code> 来让它进而满足 <code>RegexComponent</code> 并用在 Regex 构造中。</p>
|
||
<pre><code class="language-swift">
|
||
func consuming( _ input: String,
|
||
startingAt index: String.Index,
|
||
in bounds: Range<String.Index>
|
||
) throws -> (upperBound: String.Index, output: Self.RegexOutput)?
|
||
</code></pre>
|
||
<p>返回匹配停止时的上界，以及比配得到的结果本身即可。对于这一点，WWDC 22 的 <a href="https://developer.apple.com/videos/play/wwdc2022/110358">Swift Regex: Beyond the basics</a> 给了一个非常好的例子：</p>
|
||
<pre><code class="language-swift">
|
||
import Darwin
|
||
struct CDoubleParser: CustomConsumingRegexComponent {
|
||
typealias RegexOutput = Double
|
||
func consuming( _ input: String, startingAt index: String.Index, in bounds: Range<String.Index>
|
||
) throws -> (upperBound: String.Index, output: Double)? {
|
||
input[index...].withCString { startAddress in
|
||
var endAddress: UnsafeMutablePointer<CChar>!
|
||
let output = strtod(startAddress, &endAddress)
|
||
guard endAddress > startAddress else { return nil }
|
||
let parsedLength = startAddress.distance(to: endAddress)
|
||
let upperBound = input.utf8.index(index, offsetBy: parsedLength)
|
||
return (upperBound, output)
|
||
}
|
||
}
|
||
}
|
||
</code></pre>
|
||
<p>在很多情况下，我们可能会进一步地使用 <a href="https://github.com/apple/swift-evolution/blob/main/proposals/0299-extend-generic-static-member-lookup.md">protocol 中泛型上下文静态查找</a>的特性，为 <code>RegexComponent</code> 添加类型成员，以便在 <code>Regex</code> 中直接使用：</p>
|
||
<pre><code class="language-swift">
|
||
extension RegexComponent where Self == CDoubleParser {
|
||
static var cDouble: Self { CDoubleParser() }
|
||
}
|
||
</code></pre>
|
||
<p>Foundation 中的各种 parser 基本都遵循了类似的实现方式。</p>
|
||
<h2 id="匹配方式"><a class="header" href="#匹配方式">匹配方式</a></h2>
|
||
<h3 id="常见的匹配方法"><a class="header" href="#常见的匹配方法">常见的匹配方法</a></h3>
|
||
<pre><code class="language-swift">
|
||
// 匹配所有可能项，并将全部结果返回
|
||
input.matches(of: regex) // [Regex<Output>.Match]
|
||
// 匹配时返回第一个结果
|
||
input.firstMatch(of: regex) // Regex<Output>.Match?
|
||
// 整个字符串能完整匹配时才返回结果
|
||
input.wholeMatch(of: regex) // Regex<Output>.Match?
|
||
// 字符串的开始部分匹配的话返回结果
|
||
// 如果只需要判断是否匹配，使用 `start(with:)`
|
||
input.prefixMatch(of: regex) // Regex<Output>.Match?
|
||
</code></pre>
|
||
<p>匹配后得到的结果中，<code>.0</code> 返回匹配到的整个字符串，从 <code>.1</code> 开始是捕获的组：</p>
|
||
<pre><code class="language-swift">
|
||
let regex = /Welcome to (.+?), a person blog from (\d+)/
|
||
let text = "Welcome to OneV's Den, a person blog from 2011"
|
||
if let result = text.wholeMatch(of: regex) {
|
||
print("Title: (result.1)") // OneV's Den
|
||
print("Year: (result.2)") // 2011
|
||
}
|
||
</code></pre>
|
||
<p><code>Regex.Match</code> 实现了 dynamic lookup，可以使用 <code>Reference</code> 直接获取命名的捕获：</p>
|
||
<pre><code class="language-swift">
|
||
let regex = /Welcome to (?<name>.+?), a person blog from (?<year>\d+)/
|
||
let text = "Welcome to OneV's Den, a person blog from 2011"
|
||
if let result = text.wholeMatch(of: regex) {
|
||
print("Title: (result.name)") // OneV's Den
|
||
print("Year: (result.year)") // 2011
|
||
}
|
||
</code></pre>
|
||
<h3 id="基于-regex-的字符串算法操作"><a class="header" href="#基于-regex-的字符串算法操作">基于 Regex 的字符串算法/操作</a></h3>
|
||
<ul>
|
||
<li><code>input.ranges(of: regex)</code></li>
|
||
<li><code>input.replacing(regex, with: "string")</code></li>
|
||
<li><code>input.trimmingPrefix(regex)</code>
|
||
等..原来在 <code>Collection</code> 中可以针对字符串的操作，可以找到对应的 <code>Regex</code> 版本。</li>
|
||
</ul>
|
||
<h3 id="regex-变换flags"><a class="header" href="#regex-变换flags">Regex 变换/Flags</a></h3>
|
||
<p>在创建 <code>Regex</code> 后，可以使用其上的实例方法来对 <code>Regex</code> 进行部分修改。最常用的大概有：</p>
|
||
<ul>
|
||
<li><code>ignoresCase(_:)</code> - 匹配是否忽略大小写。等效于 <code>/[aeiou]/i</code> 中的 <code>i</code> flag。</li>
|
||
<li><code>anchorsMatchLineEndings(_:)</code> - <code>^</code> 和 <code>$</code> 是否也匹配每行。等效于 <code>/^[aeiou]$/m</code> 中的 <code>m</code> flag。</li>
|
||
<li><code>dotMatchesNewlines(_:)</code> - 字面量 <code>.</code> 是否应该匹配包括换行符在内的任意字符。等效于 <code>s</code> flag。</li>
|
||
</ul>
|
||
<h2 id="小结"><a class="header" href="#小结">小结</a></h2>
|
||
<p>Swift Regex 是符合 Swift 美学的正则写法，可以在标准库层面替代掉 Apple 平台上原有的被诟病已久的 <code>NSRegularExpression</code>。随着时代车轮的前行，<code>NSRegularExpression</code> 肯定将被逐渐扫进垃圾堆。
|
||
当前 Swift Regex 已经相对很完善了，它的优点非常明确：</p>
|
||
<ul>
|
||
<li>使用 DSL 的方式构建易于理解和维护的正则</li>
|
||
<li>可以与 Parser 结合使用，提供高质量的匹配
|
||
当然，在本文写作时也还存在一些不足。</li>
|
||
<li>文档不足，实际用例和社区支持也相对匮乏</li>
|
||
<li>需求的系统版本较高，近几年内可能难以完全迁移</li>
|
||
<li>不论字面量还是 DSL，暂时还不支持 <code>if</code> 等条件控制</li>
|
||
<li>Foundation 的 Parser 数量和种类不多
|
||
不过这些毒点相对都是容易改善的，个人还是十分看好 Swift Regex 的前景。特别是用来做一些简单的文本处理和本地工具的话，会非常方便。
|
||
和 Swift <code>String</code> 一样，<code>Regex</code> 从设计初期就考虑了 Unicode 安全。不过本文暂时没有涉及 Unicode 的处理，日后如果用到再继续补充。</li>
|
||
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|
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