将Python列表中的字符串值替换为特定的数值

# 原始列表
original_list = ['apple', 'banana', 'cherry', 'date']

# 定义映射关系
replacement_map = {
    'apple': 1,
    'banana': 2,
    'cherry': 3,
    'date': 4
}

# 替换字符串值为数值
def replace_strings_with_numbers(lst, mapping):
    return [mapping.get(item, item) for item in lst]

# 替换后的列表
new_list = replace_strings_with_numbers(original_list, replacement_map)
print(new_list)  # 输出: [1, 2, 3, 4]

# 使用dict.get()方法
def replace_strings_with_numbers(lst, mapping):
    return [mapping.get(item, item) for item in lst]

# 使用生成器表达式
def replace_strings_with_numbers(lst, mapping):
    return (mapping.get(item, item) for item in lst)

# 复杂条件替换
def complex_replacement(item):
    if item == 'apple':
        return 1
    elif item == 'banana':
        return 2
    else:
        return item

def replace_strings_with_numbers(lst, func):
    return [func(item) for item in lst]

new_list = replace_strings_with_numbers(original_list, complex_replacement)
print(new_list)  # 输出: [1, 2, 'cherry', 'date']