在org-mode中使用自定义乳胶导出类

Question

我试图摆脱org导出的latex文件头中的一些包。 This教程建议将以下内容添加到emacs：

的配置中

(add-to-list 'org-export-latex-classes
      '("org-article"
         "\\documentclass{org-article}
         [NO-DEFAULT-PACKAGES]
         [PACKAGES]
         [EXTRA]"
         ("\\section{%s}" . "\\section*{%s}")
         ("\\subsection{%s}" . "\\subsection*{%s}")
         ("\\subsubsection{%s}" . "\\subsubsection*{%s}")
         ("\\paragraph{%s}" . "\\paragraph*{%s}")
         ("\\subparagraph{%s}" . "\\subparagraph*{%s}"))) 

然而，当我开始emacs时，我收到错误：

Symbol's value as variable is void: org-export-latex-classes 

我还尝试将以下内容放入.org file：

#+begin_src emacs-lisp :results silent
  (add-to-list 'org-export-latex-classes
          '("per-file-class"
             "\\documentclass{scrartcl}
             [NO-DEFAULT-PACKAGES]
             [EXTRA]"
             ("\\section{%s}" . "\\section*{%s}")
             ("\\subsection{%s}" . "\\subsection*{%s}")
             ("\\subsubsection{%s}" . "\\subsubsection*{%s}")
             ("\\paragraph{%s}" . "\\paragraph*{%s}")
             ("\\subparagraph{%s}" . "\\subparagraph*{%s}")))
#+end_src

#+LaTeX_CLASS: per-file-class

但是，当我导出时，org-mode会抱怨没有名为per-file-class的类。

我如何解决这个难题？ （请注意，我没有lisp背景）

Answer 1

你需要在加载ox-latex.el之后放入（add-to-list'org-export-latex-classes ....）（这是变量所在的位置）一种方法是使用eval-after-load：

namespace Foo {

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;   



public class Program
{
    public static void Main()
    {
        var parent = new Parent {
            Children = new List<Child> { 
                new Child(),
                new Child(),
                new Child()
            }
        };

        {
        // works

        var expr = BuildLambda<Parent, IEnumerable<Child>>("Children");

        expr.Compile().Invoke(parent).ToList().ForEach(x => Console.WriteLine(x));
        }

        // works too
        {

        var expr2 = BuildLambda<Parent, IEnumerable<object>>("Children");

        expr2.Compile().Invoke(parent).ToList().ForEach(x => Console.WriteLine(x));
        }

        // and this works too
        ValidateEntity(parent);

    }


    public static void ValidateEntity<TEntity>(TEntity e) 
        where TEntity : class, new()
        {
            var propertyName = "Children";
            var propType = typeof(TEntity).GetProperty(propertyName);


            var expr = typeof(Program)
                .GetMethod("BuildLambda", BindingFlags.Public | BindingFlags.Static)
                .MakeGenericMethod(new[] { typeof(TEntity), propType.PropertyType })
                .Invoke(null, new[] {propertyName});

            // Here we invoke artificial method and inject property type there
            typeof(Program).GetMethod("ProcessExpr")
                .MakeGenericMethod(new[] { typeof(TEntity), propType.PropertyType })
                .Invoke(null, new [] { expr, e });

        }


    public static void ProcessExpr<TEntity, TValue>(Expression<Func<TEntity, TValue>> expr, TEntity parent) {
        // here we know both types
        Console.WriteLine("Yay works too!");
        ((IEnumerable<Child>)expr.Compile().Invoke(parent)).Cast<Child>().ToList().ForEach(x => Console.WriteLine(x));
    }


    public static Expression<Func<TEntity, TValue>> BuildLambda<TEntity, TValue>(string property) where TEntity : class
        {
            var param = Expression.Parameter(typeof (TEntity), "e");
            var prop = Expression.PropertyOrField(param, property);
            return Expression.Lambda<Func<TEntity, TValue>>(prop, param); 
        }
}

public class Parent {

    public List<Child> Children { get; set; }
}

public class Child { }

}

对于per-file类，您需要再次加载ox-latex，然后需要使用C-c C-c评估代码块。之后使用C-h v检查org-export-latex-classes的值，以确保它被“采用”。