help.txt

C# Script execution engine (.NET Core). Version 4.4.8.0.
Copyright (C) 2004-2020 Oleg Shilo.


<switch 1>

--help|-help|-? [<command>|<scope[:md]>|<-out:<file>>]
    Displays either generic or command specific help info.
    
       <command> - one of the supported CLI commands
       <scope>  
             `cli`    - print documentation for all CLI commands
             `syntax` - print the complete documentation for scripting syntax
             `md`     - print the documentation in GitHub markdown format
             (e.g. `-help cli:md`)
       <file>    - output file for the help content
    
    Reversed order of parameters for the command specific help is also acceptable. The all following argument
    combinations print the same help topic for 'cache' command:
    
       -help cache
       -? cache
       -cache help
       -cache ?

-e
    Compiles script into console application executable.

-ew
    Compiles script into Windows application executable (applicable only on Windows).

-c[:<0|1>]
    Executes compiled script cache (e.g. <cache dir>/script.cs.dll) if found.
    This command improves performance by avoiding compiling the script if it was not changed since last execution.
    
       -c:1|-c  - enable caching
       -c:0     - disable caching (which might be enabled globally)

-ca
    Compiles script file into cache file (e.g. <cache dir>/script.cs.dll).

-cd
    Compiles script file into assembly (.dll) in the script folder without execution.

-check
    Checks script for errors without execution.

-proj
    Shows script 'project info' - script and all its dependencies.

-vs <script>|-vs:init [index_of_detected_VS_executable]
    Generates .NET project file and opens it in Visual Studio.
    The path to the Visual Studio executable (devenv.exe) needs to be defined in the environment variable
    `CSSCRIPT_VSEXE`.
    You can let CS-Script to detect installed Visual Studio executable and interactively select the detected
    executable for integrating it with CS-Script by using `-vs:init` option.
    Alternatively, you can even ask to integrate the first detected executable with: 
          cscs -vs:init 0

-vscode
    Generates .NET project file and opens it in Visual Studio Code.
    The path to the Visual Studio Code executable (code.exe) needs to be defined in the environment variable
    `CSSCRIPT_VSCODEEXE`.

-cache[:<ls|trim|clear>]
    Performs script cache operations.
    
     ls    - lists all cache items.
     trim  - removes all abandoned cache items.
     clear - removes all cache items.

-co:<options>
    Passes compiler options directly to the language compiler.
    (e.g.  `-co:/d:TRACE` pass `/d:TRACE` option to C# compiler
     or    `-co:/platform:x86` to produce Win32 executable)

-ng|-engine:<csc|dotnet|roslyn>]
    Forces compilation to be done by one of the supported .NET engines.
      
    `dotnet` - dotnet.exe compiler; this is the most versatile compilation engine though it does have a startup
               overhead when running the script for the first time. It requires .NET SDK to be installed on the target
               system.
      
    `csc`   - csc.exe compiler; the fastest compiler available. It is not suitable for WPF scripts as csc.exe cannot
              compile XAML.
              The compilation is performed in the separate child process build.exe which is somewhat equivalent to
              VBCSCompiler.exe (build server) from .NET toolset. It requires .NET SDK to be installed on the target
              system.
              CS-Script communicates with build.exe build server via socket (default port 17001). You can control port
              value via the environment variable 'CSS_BUILDSERVER_CSC_PORT'
              Value `csc-inproc` will suppress spinning off an build server process and .NET csc.exe will be called
              directly instead. This option convenient when socket communication is undesirable for whatever reason.
              Though in this case all the performance benefits of `-ng:csc` will be lost and then you are better off
              using `-ng:dotnet` instead.
      
    `roslyn` - Microsoft.CodeAnalysis.CSharp.Scripting.dll compiler; this is the most portable compilation engine. It
               does not require .NET SDK being installed. Though it does have limitations (see documentation).
               The compilation is performed in the separate child process cscs (another instance of script engine)
               which is somewhat equivalent of VBCSCompiler.exe (build server) from .NET toolset.
               CS-Script communicates with cscs build server via socket (default port 17002). You can control port
               value via the environment variable 'CSS_BUILDSERVER_ROSLYN_PORT'
               Value `roslyn-inproc` will suppress spinning off an external process and Roslyn compiler will be hosted
               in the original process of script engine instead. This option is convenient when socket communication
               is undesirable for whatever reason. Though in this case performance will be effected on the first run
               of the script.
      
    
    (e.g. cscs -engine:dotnet sample.cs
          cscs -ng:csc sample.cs)
          cscs -ng:roslyn-inproc sample.cs)
          cscs -ng:roslyn sample.cs)

-s|-sample[:<C# version>]
     -s:7    - prints C# 7+ sample. Otherwise, it prints the default canonical 'Hello World' sample.
    (e.g. cscs -s:7 > sample.cs).

-new[:<type>] [<script name>]
    Creates a new script.
    Usage: -new[:<type>] [<otput file>]
          type - script template based on available types.
          output - location to place the generated script file(s).
    
    Type           Template
    ---------------------------------------------------
    console         Console script application (Default)
    console-vb      Console VB script application
    winform         Windows Forms (WinForms) script application
    winform-vb      Windows Forms (WinForms) VB script application
    wpf             WPF script application
    wpf-cm          Caliburn.Micro based WPF script application
    toplevel|top    Top-level class script application with no entry point
    toplevel-x      Top-level class script application with no entry point an advanced CS-Script integration samples.
     
    Legacy templates:
    auto            Auto-class (classless) script application; use 'toplevel' instead
    freestyle       Freestyle (no entry point) script application; use 'toplevel' instead
     
    Examples:
        cscs -new script
        cscs -new:toplevel script.cs
        cscs -new:console console.cs
        cscs -new:winform myapp.cs
        cscs -new:wpf hello

-code[:show] <script code>
    Executes script code directly without using a script file.
    Sample:
     
    
    cscs -code "Console.WriteLine(Environment.UserDomainName);#nConsole.WriteLine(#''%USERNAME%#'');"
    cscs -code "using System.Linq;#nSystem.Diagnostics.Process.GetProcessesByName(''notepad'').ToList().ForEach(x =>
    x.Kill());"
    cscs -code "SetEnvironmentVariable(`ntp`,`notepad.exe`, EnvironmentVariableTarget.Machine)"
    
     
    The -code argument must be the last argument in the command. The only argument that is allowed after the `<script
    code>` is `//x`
     
    Escaping special characters sometimes can be problematic as many shells have their own techniques (e.g. PowerShell
    collapses two single quote characters) that may conflict with CS-Script escaping approach.This is the reason why
    CS-Script offers multiple escape techniques.
    It can be beneficial during the troubleshooting to use `-code:show` command that outputs the received CLI
    arguments and the interpreted C# code without the execution.
     
    Since command-line interface does not allow some special characters they need to be escaped.
    
    Escaped         Interpreted character
    -------------------------------------
    #n        ->    <\n>
    #r        ->    <\r>
    #''       ->    "   
    ''        ->    "   
    #``       ->    "   
    `n        ->    <\n>
    `r        ->    <\r>
    ``        ->    "

-wait[:prompt]
    Waits for user input after the execution before exiting.
    If specified the execution will proceed with exit only after any std input is received.
    Applicable for console mode only.
    prompt - if none specified 'Press any key to continue...' will be used

-ac|-autoclass[:<0|1|2|out>]
    Legacy command: executes scripts without class definition. Use top-level statements (C# 9) scripts instead.
    
     -ac     - enables auto-class decoration (which might be disabled globally).
     -ac:0   - disables auto-class decoration (which might be enabled globally).
     -ac:1   - same as '-ac'
     -ac:2   - same as '-ac:1' and '-ac'
     -ac:out - prints auto-class decoration for a given script file. The argument must be followed by the path to
               script file.
    
     
    Automatically generates 'static entry point' class if the script doesn't define any.
     
    
        using System;
     
        void Main()
        {
            Console.WriteLine("Hello World!";
        }
     
    
    Using an alternative 'instance entry point' is even more convenient (and reliable).
    The acceptable 'instance entry point' signatures are:
     
        void main()
        void main(string[] args)
        int main()
        int main(string[] args)
     
    Note, having any active code above entry point is acceptable though it complicates the troubleshooting if such a
    code contains errors. (see https://github.com/oleg-shilo/cs-script/wiki/CLI---User-Guide#command-auto-class)
     
    By default CS-Script decorates the script by adding a class declaration statement to the start of the script
    routine and a class closing bracket to the end. This may have an unintended effect as any class declared in the
    script becomes a 'nested class'. While it is acceptable for practically all use-cases it may be undesired for just
    a few scenarios. For example, any class containing method extensions must be a top-level static class, which
    conflicts with the auto-class decoration algorithm.
     
    The solution to this problem is to allow some user code to be protected from being included in the decorated code.
    Users can achieve this by placing '//css_ac_end' statement into the code. Any user code below this statement will
    be excluded from the decoration and stay unchanged.

---------
<switch 2>

-dbg|-d
    Forces compiler to include debug information.

-l[:<0|1>]
    'local' (makes the script directory a 'current directory'). '1' is a default value.

-v|-ver|--version [output file]
    Prints CS-Script version information.

-dbgprint[:<0:1>]
    Controls whether to enable Python-like print methods (e.g. dbg.print(DateTime.Now)).
    This setting allows controlling dynamic referencing of script engine assembly containing the implementation of
    Python-like print methods `dbg.print` and derived extension methods object.print() and object.dup(). While
    `dbg.print` is extremely useful it can and lead to some referencing challenges when the script being executed is
    referencing assemblies compiled with `dbg.print` already included. The simplest way to solve this problem is to
    disable the `dbg.cs` inclusion.
    
     -dbgprint:1   enable `dbg.cs` inclusion; Same as `-dbgprint`;
     -dbgprint:0   disable `dbg.cs` inclusion;

-verbose
    Prints runtime information during the script execution.
    '-verbose2' additionally echoes compiling engine (e.g. csc.dll) input and output.
    (applicable for console clients only)

-profile
    Prints script loading performance information during the script execution.

-speed
    Prints script initialization/compilation time information of the .NET compiler. 
    You can use -ng option () 
    It is a convenient way of testing performance of the .NET distribution.

-server[:<start|stop|restart|add|remove|ping>]
    Prints the information about build server.
    Note, the server starts automatically on the script execution that is configured to use the 'csc' or 'roslyn'
    engine.
    Build server is a background process, which implements hop loading of C# compiler csc.exe. Somewhat similar to
    VBCSCompiler.exe.
    These options are only relevant if the compiler engine is set to 'csc' (see '-engine' command).
    
     -server:start   - deploys and starts build server. Useful if you want to start the server on system startup.
     -server:stop    - stops build server
     -server:restart - restarts build server
     -server:reset   - stops, re-deploys and starts build server
     -server:add     - deploys build server
     -server:remove  - removes build server files. Useful for troubleshooting.
     -server:ping    - Pins running instance (if any) of the build server
    
    The following options are only relevant if the compiler engine is set to 'roslyn' (see '-engine' command).
    Roslyn based build server variant is much simpler so it only exposes start and stop interface.
    
     -server_r:start - deploys and starts Roslyn build server
     -server_r:stop  - stops Roslyn build server
    
    And this is how you can start and stop both Roslyn and csc build servers with a single command:
    
     -servers:start - deploys and starts both Roslyn and csc build server
     -servers:stop - stops both Roslyn and csc build server

-tc
    Trace compiler input produced by CS-Script code provider CSSRoslynProvider.dll.
    It's useful when troubleshooting custom compilers (e.g. Roslyn on Linux).

-wpf[:<enable|disable|1|0>]
    Enables/disables WPF support on Windows by updating the framework name in the *.runtimeconfig.json file
    
     -wpf               - prints current enabled status
     -wpf:<enable|1>    - enables WPF support
     -wpf:<disable|0>   - disables WPF support

-config[:<option>]
    Performs various CS-Script config operations
    
     -config:none                   - ignores config file (uses default settings)
     -config:create                 - creates config file with default settings
     -config:default                - prints default config file
     -config:<raw|xml>              - prints current config file content
     -config[:ls]                   - lists/prints current config values
     -config:<name> ?               - prints help for the configuration value specified by name
     -config:get:<name>             - prints current config value
     -config::<name>                - the same as `-config:get:name`
     -config:set:<name>=<value>     - sets current config value
     -config:set:<name>=add:<value> - updates the current config value content by appending the specified value.
     -config:set:<name>=del:<value> - updates the current config value content by removing all occurrences of the
                                      specified value.
     -config:<file>                 - uses custom config file
    
     
    Note: The property name in -config:set and -config:set is case insensitive and can also contain '_' as a token
    separator that is ignored during property lookup.
    
    (e.g. cscs -config:none sample.cs
          cscs -config:default > css_VB.xml
          cscs -config:set:DefaultCompilerEngine=dotnet
          cscs -config:set:DefaultArguments=add:-ac
          cscs -config:set:default_arguments=del:-ac
          cscs -config:c:\cs-script\css_VB.xml sample.vb)

-out[:<file>]
    Forces the script to be compiled into a specific location.
    Used only for very fine hosting tuning.
    (e.g. cscs -out:%temp%\%pid%\sample.dll sample.cs

-r:<assembly 1>,<assembly N>
    Uses explicitly referenced assembly.
    It is required only for rare cases when namespace cannot be resolved into assembly.
    (e.g. `cscs /r:myLib.dll myScript.cs`).

-dir:<directory 1>,<directory N>
    Adds path(s) to the assembly probing directory list.
    You can use the reserved word 'show' as a directory name to print the configured probing directories.
    (e.g. `cscs -dir:C:\MyLibraries myScript.cs; cscs -dir:show`).

-precompiler[:<file 1>,<file N>]
    Specifies custom precompiler. This can be either script or assembly file.
    Alias - pc[:<file 1>,<file N>]
    If no file(s) specified prints the code template for the custom precompiler. The special value 'print' has the
    same effect (e.g. cscs -pc:print).
    There is a special reserved word 'nodefault' to be used as a file name. It instructs script engine to prevent
    loading any built-in precompilers like the one for removing shebang before the execution.
    (see https://www.cs-script.net/cs-script/help-legacy/precompilers.html)

-pvdr|-provider:<file>
    Location of the alternative/custom code provider assembly.
    Alias - pvdr:<file>
    If set it forces script engine to use an alternative code compiler.
     
    C#7 support is implemented via Roslyn based provider: '-pvdr:CSSRoslynProvider.dll'.If the switch is not specified
    CSSRoslynProvider.dll file will be use as a code provider if it is found in the same folder where the script
    engine is. Automatic CSSRoslynProvider.dll loading can be disabled with a special 'none' argument: -pvdr:none.
    (see https://www.cs-script.net/cs-script/help-legacy/help/non_cs_compilers.html)

-nuget[:<package|purge>]
    Installs new or updates existing NuGet package.
    This command allows light management of the NuGet packages in the CS-Script local package repository
    (%PROGRAMDATA%\CS-Script\nuget).
    The tasks are limited to installing, updating and listing the local packages.
     
    
     -nuget           - prints the list of all root packages in the repository
     -nuget:<package> - downloads and installs the latest version of the package(s). 
                        Wild cards can be used to update multiple packages. For example '-nuget:ServiceStack*' will
                        update all already installed ServiceStack packages.
                        You can also use the index of the package instead of its full name.
    
     
    Installing packages this way is an alternative to having '//css_nuget -force ...' directive in the script code as
    it may be more convenient for the user to update packages manually instead of having them updated on every script
    execution/recompilation.

-syntax
    Prints documentation for CS-Script specific C# syntax.

-commands|-cmd
    Prints list of supported commands (arguments).

---------
file
    Specifies name of a script file to be run.

params
    Specifies optional parameters for a script file to be run.

//x
    Launch debugger just before starting the script.



**************************************
Script specific syntax
**************************************
 
Engine directives:
- //css_include <file>;
- //css_import <file>[, preserve_main][, rename_namespace(<oldName>, <newName>)];
- //css_nuget [-noref] [-force[:delay]] [-ver:<version>] [-rt:<runtime>] [-ng:<nuget arguments>]
package0[,package1]..[,packageN];
- //css_args arg0[,arg1]..[,argN];
- //css_reference <file>;
- //css_precompiler <file 1>,<file 2>;
- //css_searchdir <directory>;
- //css_winapp
- //css_webapp
- //css_autoclass [style]
- //css_resource <file>[, <out_file>];
- //css_co <options>;
- //css_engine <csc|dotnet|roslyn>;
- //css_ignore_namespace <namespace>;
- //css_ac_end
- //css_prescript file([arg0][,arg1]..[,argN])[ignore];
- //css_postscript file([arg0][,arg1]..[,argN])[ignore];
------------------------------------
Engine directives can be controlled (enabled/disabled) with compiler conditional symbols and environment variables via
the inline `#if` syntax:
  //css_include #if DEBUG debug_utils.cs
  //css_dir #if (DEBUG) .\bin\Debug
  //css_reference #if PRODUCTION_PC d:\temp\build\certificates.dll
------------------------------------
The script engine also always defines special compiler conditional symbol `CS_SCRIPT`:
  #if CS_SCRIPT
       Console.WriteLine("Running as a script...");
  #endif
The script engine also defines another conditional symbol `NETCORE` to allow userto distinguish between executions
under .NET (full) and .NET Core
------------------------------------
//css_include <file>;
 
Alias - //css_inc
file - name of a script file to be included at compile-time.
 
This directive is used to include one script into another one. It is a logical equivalent of '#include' in C++. This
directive is a full but more convenient equivalent of //css_import <file>, preserve_main;
 
If a relative file path is specified with a single-dot prefix it will be automatically converted into the absolute
path with respect to the location of the file containing the directive being resolved. Otherwise it will be resolved
with respect to the process current directory.
 
If for whatever reason it is preferred to always resolve path expression with respect to the parent script location
you can configure the script engine to do it with the following command:
 
   cscs -config:set:ResolveRelativeFromParentScriptLocation = true
 
Note if you use wildcard in the imported script name (e.g. *_build.cs) the directive will only import from the first
probing directory where the matching file(s) is found. Be careful with the wide wildcard as '*.cs' as they may lead to
unpredictable behavior. For example they may match everything from the very first probing directory, which is
typically a current directory. Using more specific wildcards is arguably more practical (e.g. 'utils/*.cs',
'*Helper.cs', './*.cs')
------------------------------------
//css_import <file>[, preserve_main][, rename_namespace(<oldName>, <newName>)];
 
Alias - //css_imp
There are also another two aliases //css_include and //css_inc. They are equivalents of //css_import <file>,
preserve_main
If $this (or $this.name) is specified as part of <file> it will be replaced at execution time with the main script
full name (or file name only).
 
file            - name of a script file to be imported at compile-time.
<preserve_main> - do not rename 'static Main'
oldName         - name of a namespace to be renamed during importing
newName         - new name of a namespace to be renamed during importing
 
This directive is used to inject one script into another at compile time. Thus code from one script can be exercised
in another one.'Rename' clause can appear in the directive multiple times.
------------------------------------
 
//css_nuget [-noref] [-force[:delay]] [-ver:<version>] [-rt:<runtime>] [-ng:<nuget arguments>]
package0[,package1]..[,packageN];
 
Downloads/Installs the NuGet package. It also automatically references the downloaded package assemblies.
Note: The directive switches need to be in the order as above.
 
By default the package is not downloaded again if it was already downloaded.
If no version is specified then the highest downloaded version (if any) will be used.
Referencing the downloaded packages can only handle simple dependency scenarios when all downloaded assemblies are to
be referenced.
You should use '-noref' switch and reference assemblies manually for all other cases. For example multiple assemblies
with the same file name that target different CLRs (e.g. v3.5 vs v4.0) in the same package.
Switches:
 -noref         - switch for individual packages if automatic referencing isn't desired. 
                  You can use 'css_nuget' environment variable for further referencing package content (e.g. //css_dir
                  %css_nuget%\WixSharp\**)
 -force[:delay] - switch to force individual packages downloading even when they were already downloaded.
                  You can optionally specify delay for the next forced downloading by number of seconds since last
                  download.
                  '-force:3600' will delay it for one hour. This option is useful for preventing frequent download
                  interruptions during active script development.
 -ver:<version> - switch to download/reference a specific package version.
 -rt:<runtime>  - switch to use specific runtime binaries (e.g. '-rt:netstandard1.3').
 -ng:<args>     - switch to pass NuGet arguments for every individual package.
 
Example: //css_nuget cs-script;
         //css_nuget -ver:4.1.2 NLog
         //css_nuget -ver:"4.1.1-rc1" -rt:netstandard2.0 -ng:"-Pre -NoCache" NLog
 
This directive will install CS-Script NuGet package.
(see http://www.csscript.net/help/script_nugets.html)
------------------------------------
//css_args arg0[,arg1]..[,argN];
 
Embedded script arguments. The both script and engine arguments are allowed except "/noconfig" engine command switch.
Example: //css_args -dbg, -inmem;
This directive will always force script engine to execute the script in debug mode.
Note: the arguments must be coma separated.
------------------------------------
//css_reference <file>;
 
Alias - //css_ref
file - name of the assembly file to be loaded at run-time.
This directive is used to reference assemblies required at run time.
The assembly must be in GAC, the same folder with the script file or in the 'Script Library' folders (see 'CS-Script
settings').
 
Note if you use wildcard in the referenced assembly name (e.g. socket.*.dll) the directive will only reference from
the first probing directory where the matching file(s) is found. Be careful with the wide wildcard as '*.dll' as they
may lead to unpredictable behavior. For example they may match everything from the very first probing directory, which
is typically a current directory. Using more specific wildcards is arguably more practical (e.g. 'utils/*.dll',
'*Helper.dll', './*.dll')
 
------------------------------------
//css_precompiler <file 1>,<file 2>;
 
Alias - //css_pc
file - name of the script or assembly file implementing precompiler.
 
This directive is used to specify the CS-Script precompilers to be loaded and exercised against script at run time
just before compiling it. Precompilers are typically used to alter the script coder before the execution. Thus
CS-Script uses built-in precompiler to decorate classless scripts executed with -autoclass switch.
(see http://www.csscript.net/help/precompilers.html
------------------------------------
//css_searchdir <directory>;
 
Alias - //css_dir
directory - name of the directory to be used for script and assembly probing at run-time.
 
This directive is used to extend set of search directories (script and assembly probing).
The directory name can be a wildcard based expression.In such a case all directories matching the pattern will be this
case all directories will be probed.
The special case when the path ends with '**' is reserved to indicate 'sub directories' case. Examples:
    //css_dir packages\ServiceStack*.1.0.21\lib\net40
    //css_dir packages\**
------------------------------------
//css_winapp
 
Alias - //css_winapp
Adds search directories required for running WinForm and WPF scripts.
Note: you need to use csws.exe engine to run WPF scripts.
Alternatively you can set environment variable 'CSS_WINAPP' to non empty value and css.exe shim will redirect the
execution to the csws.exe executable.
------------------------------------
//css_webapp
 
Alias - //css_webapp
Indicates that the script app needs to be compiled against Microsoft.AspNetCore.App framework.
A typical example is a WebAPI script application.
------------------------------------
//css_autoclass [style]
 
Alias - //css_ac
OBSOLETE, use top-class native C# 9 feature instead
Automatically generates 'static entry point' class if the script doesn't define any.
 
    //css_ac
    using System;
 
    void Main()
    {
        Console.WriteLine("Hello World!");
    }
 
Using an alternative 'instance entry point' is even more convenient (and reliable).
The acceptable 'instance entry point' signatures are:
 
    void main()
    void main(string[] args)
    int main()
    int main(string[] args)
 
The convention for the classless (auto-class) code structure is as follows:
 - set of 'using' statements - classless 'main'  - user code  - optional //css_ac_end directive - optional user code
that is not a subject of auto-class decoration(see
https://github.com/oleg-shilo/cs-script/wiki/CLI---User-Guide#command-auto-class)
 
A special case of auto-class use case is a free style C# code that has no entry point 'main' at all:
 
    //css_autoclass freestyle
    using System;
 
    Console.WriteLine(Environment.Version);
 
Since it's problematic to reliable auto-detect free style auto-classes, they must be defined with the special
parameter 'freestyle' after the '//css_ac' directive
 
By default CS-Script decorates the script by adding a class declaration statement to the start of the script routine
and a class closing bracket to the end. This may have an unintended effect as any class declared in the script becomes
a 'nested class'. While it is acceptable for practically all use-cases it may be undesired for just a few scenarios.
For example, any class containing method extensions must be a top level static class, what conflicts with the
auto-class decoration algorithm.
 
An additional '//css_autoclass_end' ('//css_ac_end') directive can be used to solve this problem.
 
It's nothing else but a marker indicating the end of the code that needs to be decorated as (wrapped into) an
auto-class.
This directive allows defining top level static classes in the class-less scripts, which is required for implementing
extension methods.
 
 //css_ac
 using System;
 
 void main()
 {
     ...
 }
 
 //css_ac_end
 
 static class Extensions
 {
     static public string Convert(this string text)
     {
         ...
     }
 }
------------------------------------
//css_resource <file>[, <out_file>];
 
Alias - //css_res
file     - name of the compiled resource file (.resources) to be used with the script.
           Alternatively it can be the name of the XML resource file (.resx) that will be compiled on-fly.
out_file - Optional name of the compiled resource file (.resources) to be generated form the .resx input.If not
           supplied then the compiled file will have the same name as the input file but the file extension '.resx'
           changed to '.resources'.
 
This directive is used to reference resource file for script.
 Example: //css_res Scripting.Form1.resources;
          //css_res Resources1.resx;
          //css_res Form1.resx, Scripting.Form1.resources;
------------------------------------
//css_co <options>;
 
options - options string.
 
This directive is used to pass compiler options string directly to the language specific CLR compiling engine.
Note: 
- the options may not be compatible with the compiling engine of your choice (see //css_engine).Thus `//css_co
/define:CS_SCRIPT` will work for `csc` engine but will not for `dotnet` since it does not support /define.
- character `;` in compiler options interferes with `//css_...` directives so try to avoid it. Thus use `-d:DEBUG
-d:NET4` instead of `-d:DEBUG;NET4`
 Example: //css_co /d:TRACE pass /d:TRACE option to C# compiler
          //css_co /platform:x86 to produce Win32 executable
------------------------------------
//css_engine <csc|dotnet|roslyn>;
 
Alias - //css_ng
 
This directive is used to select compiler services for building a script into an assembly.
  dotnet - use `dotnet.exe` and on-fly .NET projects.
           This is a default compiler engine that handles well even complicated heterogeneous multi-file scripts like
           WPF scripts.
  csc    - use `csc.exe`. 
           This compiler shows much better performance. Though it is not suitable for WPF scripts.
This feature is conceptually similar to the VBCSCompiler.exe build server, which is not available in in
.NET5/.NET-Core. Even though available on .NET-Fx (Roslyn).
           Using this option can in order of magnitude improve compilation speed. However it's not suitable for
           compiling WPF scripts because csc.exe cannot compile XAML.
           While this feature useful it will be deprecated when .NET5+ starts distributing its own properlyworking
           build server VBCSCompiler.exe.
  roslyn - use `Microsoft.CodeAnalysis.CSharp.Scripting.dll` (Roslyn). 
           This compiler shows good performance and does not require .NET SDK. Though it is not suitable for WPF
           scripts. See [this wiki](https://github.com/oleg-shilo/cs-script/wiki/Choosing-Compiler-Engine) for
           details.
 
 Example: //css_engine csc
------------------------------------
//css_ignore_namespace <namespace>;
 
Alias - //css_ignore_ns
namespace - name of the namespace. Use '*' to completely disable namespace resolution
 
This directive is used to prevent CS-Script from resolving the referenced namespace into assembly.
------------------------------------
//css_ac_end
 
This directive is only applicable for class-less scripts executed with '-autoclass' CLI argument. It's nothing else
but a marker indicating the end of the code that needs to be decorated as (wrapped into) an auto-class.
This directive allows achieving top level static classes in the class-less scripts, which is required for implementing
extension methods.
 
 //css_args -acutoclass
 using System;
 
 void main()
 {
     ...
 }
 
 //css_ac_end
 
 static class Extensions
 {
     static public void Convert(this string text)
     {
         ...
     }
 }
------------------------------------
//css_prescript file([arg0][,arg1]..[,argN])[ignore];
//css_postscript file([arg0][,arg1]..[,argN])[ignore];
 
Aliases - //css_pre and //css_post
file    - script file (extension is optional)
arg0..N - script string arguments
ignore  - continue execution of the main script in case of error
 
These directives are used to execute secondary pre- and post-execution scripts.
If $this (or $this.name) is specified as arg0..N it will be replaced at execution time with the main script full name
(or file name only).
You may find that in many cases precompilers (//css_pc and -pc) are a more powerful and flexible alternative to the
pre-execution script.
------------------------------------
 
Note the script engine always sets the following environment variables:
 'pid'                     - host processId (e.g. Environment.GetEnvironmentVariable("pid")
 'CSScriptRuntime'         - script engine version
 'CSScriptRuntimeLocation' - script engine location
 'cscs_exe_dir'            - script engine directory
 'EntryScript'             - location of the entry script
 'EntryScriptAssembly'     - location of the compiled script assembly
 'location:<asm_hash>'    - location of the compiled script assembly.
 
This variable is particularly useful as it allows finding the compiled assembly file from the inside of the script
code. Even when the script loaded in-memory (InMemoryAssembly setting) but not from the original file. (e.g. var
location = Environment.GetEnvironmentVariable("location:" + Assembly.GetExecutingAssembly().GetHashCode()); 
 
Note that by default setting of 'location:<asm_hash>' is disabled. You can enable it by calling 
'CSScript.EnableScriptLocationReflection = true'.
 
The following is the optional set of environment variables that the script engine uses to improve the user experience:
 
 'CSS_NUGET' 
      location of the NuGet packages scripts can load/reference
 
 'CSSCRIPT_ROOT'
      script engine location. Used by the engine to locate dependencies (e.g. resgen.exe). Typically this variable is
      during the CS-Script installation.
 
 'CSSCRIPT_CONSOLE_ENCODING_OVERWRITE'
      script engine output encoding if the one from the css_confix.xml needs to be overwritten.
 
 'CSSCRIPT_INC'
      a system wide include directory for the all frequently used user scripts.
 
 'CSSCRIPT_CSC_CMD_LOG'
      the location of the log file that will be created during the script execution with the 'csc' compiler engine.the
      file will contain the command line that is used to start `csc.exe` to compile the script. This behavior is
      useful for the advanced debugging scenarios. Of the environment variable is not set or the value is not a valid
      file path then no log file will be created.
---------
During the script execution CS-Script always injects a little object inspector class 'dbg'. This class contains static
printing methods that mimic Python's 'print()'. It is particularly useful for object inspection in the absence of a
proper debugger.
 
Examples:
  dbg.print("Now:", DateTime.Now)        - prints concatenated objects.
  dbg.print(DateTime.Now)                - prints object and values of its properties.
  dbg.printf("Now: {0}", DateTime.Now)   - formats and prints object and values of its fields and properties.
---------
 
Any directive has to be written as a single line in order to have no impact on compiling by CLI compliant compiler.It
also must be placed before any namespace or class declaration.
 
---------
Example:
 
 //css_include web_api_host.cs;
 //css_reference media_server.dll;
 //css_nuget Newtonsoft.Json;
 
 using System;
 using static dbg;
 
 class MediaServer
 {
     static void Main(string[] args)
     {
         print(args);
 
         WebApi.SimpleHost(args)
               .StartAsConosle("http://localhost:8080");
   }
 }
 
Or shorter form:
 
 //css_args -ac
 //css_inc web_api_host.cs
 //css_ref media_server.dll
 //css_nuget Newtonsoft.Json
 
 using System;
 
 void main(string[] args)
 {
     print(args);
 
     WebApi.SimpleHost(args)
           .StartAsConosle("http://localhost:8080");
 }
 
---------
 Project Website: https://github.com/oleg-shilo/cs-script