package.json 中的scripts的脚本中--这符号表示啥意思

Z时代
2024-01-10
分类：IT

这里面的--表示啥意思
图片描述

回答：

命令的参数，比如webpack --config webpack.config.js表示webpack的config参数的值为webpack.config.js。

但是并不是所有的命令参数都是这个格式，详细可以查看该命令的文档。

以webpack为例

webpack-cli 3.3.8 Usage: webpack-cli [options] webpack-cli [options] --entry <entry> --output <output> webpack-cli [options] <entries...> --output <output> webpack-cli <command> [options] For more information, see https://webpack.js.org/api/cli/. Config options: --config Path to the config file [string] [default: webpack.config.js or webpackfile.js] --config-register, -r Preload one or more modules before loading the webpack configuration [array] [default: module id or path] --config-name Name of the config to use [string] --env Environment passed to the config, when it is a function --mode Enable production optimizations or development hints. [choices: "development", "production", "none"] Basic options: --context The base directory (absolute path!) for resolving the `entry` option. If `output.pathinfo` is set, the included pathinfo is shortened to this directory. [string] [default: The current directory] --entry The entry point(s) of the compilation. [string] --watch, -w Enter watch mode, which rebuilds on file change. [boolean] --debug Switch loaders to debug mode [boolean] --devtool A developer tool to enhance debugging. [string] -d shortcut for --debug --devtool eval-cheap-module-source-map --output-pathinfo [boolean] -p shortcut for --optimize-minimize --define process.env.NODE_ENV="production" [boolean] --progress Print compilation progress in percentage [boolean] Module options: --module-bind Bind an extension to a loader [string] --module-bind-post Bind an extension to a post loader [string] --module-bind-pre Bind an extension to a pre loader [string] Output options: --output, -o The output path and file for compilation assets --output-path The output directory as **absolute path** (required). [string] [default: The current directory] --output-filename Specifies the name of each output file on disk. You must **not** specify an absolute path here! The `output.path` option determines the location on disk the files are written to, filename is used solely for naming the individual files. [string] [default: [name].js] --output-chunk-filename The filename of non-entry chunks as relative path inside the `output.path` directory. [string] [default: filename with [id] instead of [name] or [id] prefixed] --output-source-map-filename The filename of the SourceMaps for the JavaScript files. They are inside the `output.path` directory. [string] --output-public-path The `publicPath` specifies the public URL address of the output files when referenced in a browser. [string] --output-jsonp-function The JSONP function used by webpack for async loading of chunks. [string] --output-pathinfo Include comments with information about the modules. [boolean] --output-library Expose the exports of the entry point as library [array] --output-library-target Type of library [string] [choices: "var", "assign", "this", "window", "self", "global", "commonjs", "commonjs2", "commonjs-module", "amd", "umd", "umd2", "jsonp"] Advanced options: --records-input-path Store compiler state to a json file. [string] --records-output-path Load compiler state from a json file. [string] --records-path Store/Load compiler state from/to a json file. This will result in persistent ids of modules and chunks. An absolute path is expected. `recordsPath` is used for `recordsInputPath` and `recordsOutputPath` if they left undefined.[string] --define Define any free var in the bundle [string] --target Environment to build for [string] --cache Cache generated modules and chunks to improve performance for multiple incremental builds. [boolean] [default: It's enabled by default when watching] --watch-stdin, --stdin Stop watching when stdin stream has ended [boolean] --watch-aggregate-timeout Delay the rebuilt after the first change. Value is a time in ms. [number] --watch-poll Enable polling mode for watching [string] --hot Enables Hot Module Replacement [boolean] --prefetch Prefetch this request (Example: --prefetch ./file.js) [string] --provide Provide these modules as free vars in all modules (Example: --provide jQuery=jquery) [string] --labeled-modules Enables labeled modules [boolean] --plugin Load this plugin [string] --bail Report the first error as a hard error instead of tolerating it. [boolean] [default: null] --profile Capture timing information for each module. [boolean] [default: null] Resolving options: --resolve-alias Redirect module requests [string] --resolve-extensions Redirect module requests [array] --resolve-loader-alias Setup a loader alias for resolving [string] Optimizing options: --optimize-max-chunks Try to keep the chunk count below a limit --optimize-min-chunk-size Minimal size for the created chunk --optimize-minimize Enable minimizing the output. Uses optimization.minimizer. [boolean] Stats options: --color, --colors Force colors on the console [boolean] [default: (supports-color)] --no-color, --no-colors Force no colors on the console [boolean] --sort-modules-by Sorts the modules list by property in module [string] --sort-chunks-by Sorts the chunks list by property in chunk [string] --sort-assets-by Sorts the assets list by property in asset [string] --hide-modules Hides info about modules [boolean] --display-exclude Exclude modules in the output [string] --display-modules Display even excluded modules in the output [boolean] --display-max-modules Sets the maximum number of visible modules in output [number] --display-chunks Display chunks in the output [boolean] --display-entrypoints Display entry points in the output [boolean] --display-origins Display origins of chunks in the output [boolean] --display-cached Display also cached modules in the output [boolean] --display-cached-assets Display also cached assets in the output [boolean] --display-reasons Display reasons about module inclusion in the output [boolean] --display-depth Display distance from entry point for each module [boolean] --display-used-exports Display information about used exports in modules (Tree Shaking) [boolean] --display-provided-exports Display information about exports provided from modules [boolean] --display-optimization-bailout Display information about why optimization bailed out for modules [boolean] --display-error-details Display details about errors [boolean] --display Select display preset [string] [choices: "", "verbose", "detailed", "normal", "minimal", "errors-only", "none"] --verbose Show more details [boolean] --info-verbosity Controls the output of lifecycle messaging e.g. Started watching files... [string] [choices: "none", "info", "verbose"] [default: "info"] --build-delimiter Display custom text after build output[string] Options: --help, -h Show help [boolean] --version, -v Show version number [boolean] --silent Prevent output from being displayed in stdout [boolean]

--json, -j Prints the result as JSON.

但是Java的是一个横杠

Usage: java [-options] class [args...]
           (to execute a class)
   or  java [-options] -jar jarfile [args...]
           (to execute a jar file)
where options include:
    -d32          use a 32-bit data model if available
    -d64          use a 64-bit data model if available
    -server       to select the "server" VM
    -zero         to select the "zero" VM
    -dcevm        to select the "dcevm" VM
                  The default VM is server,
                  because you are running on a server-class machine.
    -cp <class search path of directories and zip/jar files>
    -classpath <class search path of directories and zip/jar files>
                  A : separated list of directories, JAR archives,
                  and ZIP archives to search for class files.
    -D<name>=<value>
                  set a system property
    -verbose:[class|gc|jni]
                  enable verbose output
    -version      print product version and exit
    -version:<value>
                  Warning: this feature is deprecated and will be removed
                  in a future release.
                  require the specified version to run
    -showversion  print product version and continue
    -jre-restrict-search | -no-jre-restrict-search
                  Warning: this feature is deprecated and will be removed
                  in a future release.
                  include/exclude user private JREs in the version search
    -? -help      print this help message
    -X            print help on non-standard options
    -ea[:<packagename>...|:<classname>]
    -enableassertions[:<packagename>...|:<classname>]
                  enable assertions with specified granularity
    -da[:<packagename>...|:<classname>]
    -disableassertions[:<packagename>...|:<classname>]
                  disable assertions with specified granularity
    -esa | -enablesystemassertions
                  enable system assertions
    -dsa | -disablesystemassertions
                  disable system assertions
    -agentlib:<libname>[=<options>]
                  load native agent library <libname>, e.g. -agentlib:hprof
                  see also, -agentlib:jdwp=help and -agentlib:hprof=help
    -agentpath:<pathname>[=<options>]
                  load native agent library by full pathname
    -javaagent:<jarpath>[=<options>]
                  load Java programming language agent, see java.lang.instrument
    -splash:<imagepath>
                  show splash screen with specified imageSee http://www.oracle.com/technetwork/java/javase/documentation/index.html for more details.