为什么这个正则表达式没有捕获最后一个输入？

Question

我不明白我写的这个正则表达式出了什么问题。

import re

# Define the input strings
inputs = [
    "exmpl-staging-1234-e2e-1707336983872",
    "exmpl-staging-1234-e2e-1706336983875",
    "exmpl-staging-main-e2e-1707336983878",
    "exmpl-demo-e2e-1707336983878",
    "exmpl-production-e2e-1707336983875",
    "exmpl-staging-2345",
    "exmpl-staging-1234",
    "exmpl-staging-1234-my-case-title",
    "exmpl-staging-1234-my-case-title-e2e-1707336983872"
]

# Define the regex pattern
pattern = re.compile(r'^exmpl-(?P<type>main|staging|demo|production)(?:-(?P<case>\d+|main))?(?:-(?P<title>(?!e2e-\d+).+))?(?:-e2e-(?P<timestamp>\d+))?$')

# Initialize a list to store the extracted data
extracted_data = []

# Loop through the input strings
for input_str in inputs:
    # Match the pattern against the input string
    match = pattern.match(input_str)

    # Extract the required information
    if match:
        extracted_data.append({
            'Input': input_str,
            'Type': match.group('type'),
            'Case': match.group('case') if match.group('case') else 'none',
            'Title': match.group('title') if match.group('title') else 'none',
            'Timestamp': match.group('timestamp') if match.group('timestamp') else 'none'
        })
    else:
        extracted_data.append({
            'Input': input_str,
            'Type': 'No match found',
            'Case': 'No match found',
            'Title': 'No match found',
            'Timestamp': 'No match found'
        })

print("| Input                                              | Type       | Case    | Title                                | Timestamp       |")
print("|----------------------------------------------------|------------|---------|--------------------------------------|-----------------|")
for data in extracted_data:
    print("| {:<50} | {:<10} | {:<7} | {:<36} | {:<15} |".format(data['Input'], data['Type'], data['Case'], data['Title'], data['Timestamp']))

这是它提供的输出：

| Input                                              | Type       | Case    | Title                                | Timestamp       |
|----------------------------------------------------|------------|---------|--------------------------------------|-----------------|
| exmpl-staging-1234-e2e-1707336983872               | staging    | 1234    | none                                 | 1707336983872   |
| exmpl-staging-1234-e2e-1706336983875               | staging    | 1234    | none                                 | 1706336983875   |
| exmpl-staging-main-e2e-1707336983878               | staging    | main    | none                                 | 1707336983878   |
| exmpl-demo-e2e-1707336983878                       | demo       | none    | none                                 | 1707336983878   |
| exmpl-production-e2e-1707336983875                 | production | none    | none                                 | 1707336983875   |
| exmpl-staging-2345                                 | staging    | 2345    | none                                 | none            |
| exmpl-staging-1234                                 | staging    | 1234    | none                                 | none            |
| exmpl-staging-1234-my-case-title                   | staging    | 1234    | my-case-title                        | none            |
| exmpl-staging-1234-my-case-title-e2e-1707336983872 | staging    | 1234    | my-case-title-e2e-1707336983872      | none            |

它按预期工作，直到最后一个

input

，其中

timestamp

为空，并且

timestamp

被错误地捕获为

title

组的一部分。我在这里做错了什么？

Answer 1

使title组变得非贪婪（Regex101）：

^exmpl-(?P<type>main|staging|demo|production)(?:-(?P<case>\d+|main))?(?:-(?P<title>(?!e2e-\d+).+?))?(?:-e2e-(?P<timestamp>\d+))?$

---

import re

# Define the input strings
inputs = [
    "exmpl-staging-1234-e2e-1707336983872",
    "exmpl-staging-1234-e2e-1706336983875",
    "exmpl-staging-main-e2e-1707336983878",
    "exmpl-demo-e2e-1707336983878",
    "exmpl-production-e2e-1707336983875",
    "exmpl-staging-2345",
    "exmpl-staging-1234",
    "exmpl-staging-1234-my-case-title",
    "exmpl-staging-1234-my-case-title-e2e-1707336983872",
]

# Define the regex pattern
pattern = re.compile(
    r"^exmpl-(?P<type>main|staging|demo|production)(?:-(?P<case>\d+|main))?(?:-(?P<title>(?!e2e-\d+).+?))?(?:-e2e-(?P<timestamp>\d+))?$"
)

# Initialize a list to store the extracted data
extracted_data = []

# Loop through the input strings
for input_str in inputs:
    # Match the pattern against the input string
    match = pattern.match(input_str)

    # Extract the required information
    if match:
        extracted_data.append(
            {
                "Input": input_str,
                "Type": match.group("type"),
                "Case": match.group("case") if match.group("case") else "none",
                "Title": match.group("title") if match.group("title") else "none",
                "Timestamp": match.group("timestamp")
                if match.group("timestamp")
                else "none",
            }
        )
    else:
        extracted_data.append(
            {
                "Input": input_str,
                "Type": "No match found",
                "Case": "No match found",
                "Title": "No match found",
                "Timestamp": "No match found",
            }
        )

print(
    "| Input                                              | Type       | Case    | Title                                | Timestamp       |"
)
print(
    "|----------------------------------------------------|------------|---------|--------------------------------------|-----------------|"
)
for data in extracted_data:
    print(
        "| {:<50} | {:<10} | {:<7} | {:<36} | {:<15} |".format(
            data["Input"], data["Type"], data["Case"], data["Title"], data["Timestamp"]
        )
    )

打印：

| Input                                              | Type       | Case    | Title                                | Timestamp       |
|----------------------------------------------------|------------|---------|--------------------------------------|-----------------|
| exmpl-staging-1234-e2e-1707336983872               | staging    | 1234    | none                                 | 1707336983872   |
| exmpl-staging-1234-e2e-1706336983875               | staging    | 1234    | none                                 | 1706336983875   |
| exmpl-staging-main-e2e-1707336983878               | staging    | main    | none                                 | 1707336983878   |
| exmpl-demo-e2e-1707336983878                       | demo       | none    | none                                 | 1707336983878   |
| exmpl-production-e2e-1707336983875                 | production | none    | none                                 | 1707336983875   |
| exmpl-staging-2345                                 | staging    | 2345    | none                                 | none            |
| exmpl-staging-1234                                 | staging    | 1234    | none                                 | none            |
| exmpl-staging-1234-my-case-title                   | staging    | 1234    | my-case-title                        | none            |
| exmpl-staging-1234-my-case-title-e2e-1707336983872 | staging    | 1234    | my-case-title                        | 1707336983872   |