注释转换-白红宇

注释转换

阅读量：774 次

发布时间：2019-03-24

本文共 2993 字，大约阅读时间需要 9 分钟。

输入程序的目标是将源文件中C风格的注释转换为C++风格的注释，并将结果保存到另一个文件中。通过对原有注释的识别和处理，程序能够按照目标语言的注释风格进行转换。

示例代码解析

#include 
   
    #pragma warning(disable:4996)typedef enum Condition {    NOT_ANNOTATION,    MAYBE_IN_ANNOTATION,    C_ANNOTATION,    CPP_ANNOTATION,    MAYBE_OUT_ANNOTATION} Condition;int main() {    FILE *pIn = fopen("input.c", "rt");    if (pIn == NULL) {        perror("fopen test");        return 1;    }    FILE *pOut = fopen("output.c", "wt");    if (pOut == NULL) {        fclose(pIn);        perror("fopen out");        return 1;    }    char ch;    Condition state = NOT_ANNOTATION;    do {        ch = fgetc(pIn);        switch (state) {            case NOT_ANNOTATION:                if (ch == '/') {                    state = MAYBE_IN_ANNOTATION;                    fputc(ch, pOut);                } else {                    state = NOT_ANNOTATION;                    fputc(ch, pOut);                }                break;            case MAYBE_IN_ANNOTATION:                if (ch == '/') {                    state = CPP_ANNOTATION;                    fputc(ch, pOut);                } else if (ch == '*') {                    state = C_ANNOTATION;                    fputc('/', pOut);                } else {                    state = NOT_ANNOTATION;                    fputc(ch, pOut);                }                break;            case CPP_ANNOTATION:                if (ch == '\n') {                    state = NOT_ANNOTATION;                    fputc(ch, pOut);                } else {                    fputc(ch, pOut);                }                break;            case C_ANNOTATION:                if (ch == '*') {                    state = MAYBE_OUT_ANNOTATION;                } else {                    fputc(ch, pOut);                    if (ch == '\n') {                        fprintf(pOut, "//");                    }                }                break;            case MAYBE_OUT_ANNOTATION:                if (ch == '*') {                    fputc('*', pOut);                    state = MAYBE_OUT_ANNOTATION;                } else if (ch == '/') {                    char nextch = fgetc(pIn);                    if (nextch != '\n') {                        fputc('\n', pOut);                    }                    ungetc(nextch, pIn);                    state = NOT_ANNOTATION;                } else {                    fputc('*', pOut);                    fputc(ch, pOut);                    state = C_ANNOTATION;                }                break;        }    } while (ch != EOF);    fclose(pOut);    fclose(pIn);    return 0;}

转换逻辑说明

状态枚举：定义了五种状态，分别为未注释（NOT_ANNOTATION）、可能进入注释（MAYBE_IN_ANNOTATION）、C风格注释（C_ANNOTATION）、C++风格注释（CPP_ANNOTATION）以及可能出注释（MAYBE_OUT_ANNOTATION）。

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