python - 如何使用 python 从给定文件中提取行 block

Question

我有一个这样的文件

grouping data-rate-parameters {
    description
      "Data rate configuration parameters.";
    reference
      "ITU-T G.997.2 clause 7.2.1.";

    leaf maximum-net-data-rate {
      type bbf-yang:data-rate32;
      default "4294967295";
      description
        "Defines the value of the maximum net data rate (see clause
         11.4.2.2/G.9701).";
      reference
        "ITU-T G.997.2 clause 7.2.1.1 (MAXNDR).";
    }

      leaf psd-level {
        type psd-level;
        description
          "The PSD level of the referenced sub-carrier.";
      }
    }
  }

  grouping line-spectrum-profile {
    description
      "Defines the parameters contained in a line spectrum
       profile.";

    leaf profiles {
      type union {
        type enumeration {
          enum "all" {
            description
              "Used to indicate that all profiles are allowed.";
          }
        }
        type profiles;
      }

这里我想提取每个叶子 block 。例如，叶最大净数据速率 block 是

leaf maximum-net-data-rate {
          type bbf-yang:data-rate32;
          default "4294967295";
          description
            "Defines the value of the maximum net data rate (see clause
             11.4.2.2/G.9701).";
          reference
            "ITU-T G.997.2 clause 7.2.1.1 (MAXNDR).";
        }

像这样我想提取

我尝试使用这段代码，这里基于大括号('{')的计数，我试图读取该 block

with open(r'file.txt','r') as f:
    leaf_part = []
    count = 0
    c = 'psd-level'
    for line in f:
        if 'leaf %s {'%c in line:
                    cur_line=line
                    for line in f:
                        pre_line=cur_line
                        cur_line=line
                        if '{' in pre_line:
                            leaf_part.append(pre_line)
                            count+=1
                        elif '}' in pre_line:
                            leaf_part.append(pre_line)
                            count-=1
                        elif count==0:
                            break
                        else:
                            leaf_part.append(pre_line)

它适用于leaf max-net-data-rate，但不适用于leaf psd-level

在对leaf psd-level进行操作时，它也会显示出 block 线。

帮助我完成这个任务。

Answer 1

它只需要在你的break循环中进行简单的编辑，因为多个右括号'}'你的计数已经是负数，因此你需要用

更改该行

elif count<=0:
    break

但它仍然在您的列表中附加多个大括号，因此您可以通过保留左括号的记录来处理它，我更改了代码如下:

with open(r'file.txt','r') as f:
    leaf_part = []
    braces_record = []
    count = 0
    c = 'psd-level'
    for line in f:
        if 'leaf %s {'%c in line:
            braces_record.append('{')
            cur_line=line
            for line in f:
                pre_line=cur_line
                cur_line=line
                if '{' in pre_line:
                    braces_record.append('{')
                    leaf_part.append(pre_line)
                    count+=1
                elif '}' in pre_line:
                    try:
                        braces_record.pop()
                        if len(braces_record)>0:
                            leaf_part.append(pre_line)
                    except:
                        pass
                    count-=1
                elif count<=0:
                    break
                elif '}' not in pre_line:
                    leaf_part.append(pre_line)

以上代码的结果:

      leaf psd-level {
        type psd-level;
        description
          "The PSD level of the referenced sub-carrier.";
  }