机器视觉 export_def算子

Posted 2021-06-28 沧海一笑-dj

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00. 目录

文章目录

01. 概述

export_def - 将任意文本插入到程序的导出代码中。

02. 签名

export_def( : : Position, Declaration : )

03. 描述

export_def允许定义逐行写入要导出{项目或程序}的输出文件的{代码行或文本块}。

参数Position控制了在声明中给出的文本的位置。支持以下选项：

‘in_place’ - ＃
文本插入到实际位置的过程中，即在相邻的程序行之间。

‘at_file_begin’ - ＃^^
文本在导出文件的最开始处导出。

‘before_procedure’ - ＃^
文本在它定义的程序之前导出。

‘after_procedure’ - ＃$
文本在定义的程序之后导出。

‘at_file_end’ - ＃$$
文本在导出文件的最后被导出。

在程序清单中，export_def不是以正常的算子语法表示，而是由一个特殊的字符序列标记。该行中的第一个字符是导出标记＃，后面可以跟上面列出的位置标记。如果在全文编辑器中输入一个导出定义，请注意在＃之前不能有空格。

为了更好的可读性，导出字符序列后面可以跟着一个空格字符，该字符不会被解释为导出文本的一部分。所有其他的内容被添加到导出。

对于在当前程序中导出的行，导出将获得与当前程序行相同的缩进。但有一个例外：如果导出文本在导出标记或可选空间之后立即以＃开始，则导出文本不会缩进，例如：

for Index := 1 to 5 by 1
# #ifdef MY_SWITCH
# int cnt = 100;
  * an optional code block
# #endif
endfor

导出成

proc (...)
{
  ...
  for (...)
  {
#ifdef MY_SWITCH
    int cnt = 100;
    // an optional block
#endif
  }
  ...
}

导出定义可以像任何普通算子一样被激活和取消激活。取消激活的导出定义不会导出。

原文描述：

export_def allows to define code lines or text blocks that are written verbatim into the output file of a procedure or program that is exported.

The parameter Position controls the placement of the text given in Declaration. The following options are supported:

‘in_place’ - #
The text is inserted in the procedure at the actual place, i.e., inbetween the neighboring program lines.

‘at_file_begin’ - #^^
The text is exported at the very beginning of the exported file.

‘before_procedure’ - #^
The text is exported immediately before the procedure it is defined in.

‘after_procedure’ - #$
The text is exported immediately after the procedure it is defined in.

‘at_file_end’ - #$$
The text is exported at the very end of the exported file.

In the program listing, export_def is not represented in normal operator syntax but marked by a special character sequence. The first character within the line is the export marker # that can be followed by a position marker as listed above. If entering an export definition in the full text editor, please note that there must not be any spaces before #.

For better readability, the export character sequence may be followed by one space character that is not interpreted as part of the export text. All additional spaces are added to the export.

For lines that are exported within the current procedure, the export gets the same indentation as the current program lines get. There is one exception: if the export text starts with # immediately after the export markers or the optional space, the export text will not be indented at all。