Python 3-索引器错误：字符串索引超出范围

我目前正在用Python3.6创建一种编程语言，出于某种原因，下面的代码生成一个索引器：字符串索引超出范围

当我尝试在Windows批处理文件中执行以下代码时：

@echo off
python run-file.py test.ros
pause

但我得到了以下输出：

Traceback (most recent call last):
  File "run-file.py", line 16, in <module>
    if not(value[1][0] == "!") and ignoreline == False:
IndexError: string index out of range
Press any key to continue . . .

syntax.py文件如下所示：

from sys import argv as args
from sys import exit as quit
import syntax

try:
    args[1]
except IndexError:
    print("ERROR: No ROS Code file provided in execution arguments")
    print("Ensure the execution code looks something like this: python run-file.py test.ros")

with open(args[1]) as f:
    ignoreline = False
    content = f.readlines()
    content = [x.strip() for x in content]
    for value in enumerate(content):
        if not(value[1][0] == "!") and ignoreline == False:
            firstpart = value[1].split(".")[0]
            lenoffirstpart = len(value[1].split(".")[0])
            afterpart = str(value[1][lenoffirstpart + 1:])
            apwithcomma = afterpart.replace(".", "', '")
            preprint = str(firstpart + "(" + apwithcomma + ")")
            printtext = preprint.replace("(", "('")
            lastprinttext = printtext.replace(")", "')")
            try:
                exec(str("syntax." + lastprinttext))
            except Exception as e:
                template = "ERROR: An error of type {0} occured while running line {1} because {2}"
                message = template.format(
                    type(e).__name__, str(value[0] + 1), str(e.args[0]))
                print(message)
                quit(1)
        elif content[value[0]][0] == "!!!":
            ignoreline = not(ignoreline)

quit(0)

def print_message(contents=''):
    print(contents)

! This is a single line comment

!!!
This line should be ignored
and this one as well
!!!

print_message.Hello World

test.ros文件如下所示：

from sys import argv as args
from sys import exit as quit
import syntax

try:
    args[1]
except IndexError:
    print("ERROR: No ROS Code file provided in execution arguments")
    print("Ensure the execution code looks something like this: python run-file.py test.ros")

with open(args[1]) as f:
    ignoreline = False
    content = f.readlines()
    content = [x.strip() for x in content]
    for value in enumerate(content):
        if not(value[1][0] == "!") and ignoreline == False:
            firstpart = value[1].split(".")[0]
            lenoffirstpart = len(value[1].split(".")[0])
            afterpart = str(value[1][lenoffirstpart + 1:])
            apwithcomma = afterpart.replace(".", "', '")
            preprint = str(firstpart + "(" + apwithcomma + ")")
            printtext = preprint.replace("(", "('")
            lastprinttext = printtext.replace(")", "')")
            try:
                exec(str("syntax." + lastprinttext))
            except Exception as e:
                template = "ERROR: An error of type {0} occured while running line {1} because {2}"
                message = template.format(
                    type(e).__name__, str(value[0] + 1), str(e.args[0]))
                print(message)
                quit(1)
        elif content[value[0]][0] == "!!!":
            ignoreline = not(ignoreline)

quit(0)

def print_message(contents=''):
    print(contents)

! This is a single line comment

!!!
This line should be ignored
and this one as well
!!!

print_message.Hello World

问题似乎出现在run-file.py文件的第16行：

我已经尝试过用值[1][0]替换值[1][0]，并用括号替换其他组合，但都没有用

似乎当我尝试打印值时，它的行为与预期一致，并给了我！这是test.ros文件的第一个字符，但由于某种原因，它在if语句中会引发异常

如果您想要更多的源代码，可以在Github上找到包含所有文件的确切提交

更新/解决方案

---

非常感谢并帮助我解决我的问题。您可以查看我所做的更改，这是因为test.ros中的第2行是空的

在本例中，您将创建以下内容：

['! This is a single line comment',
 '',
 '!!!',
 'This line should be ignored',
 'and this one as well',
 '!!!',
 '',
 'print_message.Hello World']

当您尝试访问内容[1][0]时，会得到一个索引器，因为它是一个空字符串

尝试通过向列表中添加if来删除内容中的空行：

content = [x.strip() for x in content if x.strip()]

---

您应该立即解压缩enumerate的返回元组：对于索引，enumeratecontent中的值：。然后检查值是否以开始！喜欢值。从“！”开始。这将防止空值上的索引错误。谢谢您的建议。我已经把你的建议和Idanmel的建议结合起来了，现在效果很好，谢谢！我已将代码行添加到相应的位置。是的！它确实奏效了。我已经发布了一个概述我所做更改的答案。@RichieBendall不要发布您修复的代码。如果你找到一个有用的答案，接受它：好的，我已经接受了你的帖子作为答案。谢谢你指出这一点！