Interpreter_Exercise.c

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#include <errno.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
#include "Interpreter_Interpreter.h"
#include "Interpreter_Exercise.h"
 
//=============================================================================
//=============================================================================
 
static int sentenceTokens0[] = { 39, 18, 17, 27,  2,  7, QUESTION, EOL };
 
static int sentenceTokens1[] = { 32, 17,  1,  0, 34,  2,   1,  37, QUESTION, EOL };
 
static int sentenceTokens2[] = { 36, 17,  8,  5, 32,  2,  18,   7, QUESTION, EOL };
 
static int sentenceTokens3[] = { 11, 12, 17,  9, 36, 12,   1,   6,  20, PERIOD, EOL };
 
static int sentenceTokens4[] = { 26, 27,  7, 21, 36, 17,  27,  10, QUESTION, EOL };
 
static int sentenceTokens5[] = { 23, 28, 32, 26, 32, 18,  10, PERIOD, EOL };
 
static int* _sentenceTokenLists[] = {
    sentenceTokens0,
    sentenceTokens1,
    sentenceTokens2,
    sentenceTokens3,
    sentenceTokens4,
    sentenceTokens5,
    NULL
};
 
 
static const char* _TokensToString(int* tokens)
{
    static char buffer[256] = { 0 };
 
    memset(buffer, 0, sizeof(buffer));
 
    buffer[0] = '[';
    for (size_t index = 0; tokens[index] != EOL; ++index)
    {
        char numBuffer[6] = { 0 };
        int num_chars = snprintf(numBuffer, sizeof(numBuffer), "%3d", tokens[index]);
        if (num_chars <= 0)
        {
            int errorCode = errno;
            printf("  Error (%d)!  snprintf() failed in _TokensToString(): %s!\n", errorCode,
                strerror(errorCode));
            break;
        }
        strcat(buffer, numBuffer);
        if (tokens[index + 1] != EOL)
        {
            strcat(buffer, ", ");
        }
    }
    strcat(buffer, "]");
 
    return buffer;
}
 
 
//=============================================================================
//=============================================================================
 
// ! [Using Interpreter in C]
void Interpreter_Exercise(void)
{
    printf("\nInterpreter Exercise\n");
 
    for (size_t sentenceIndex = 0; _sentenceTokenLists[sentenceIndex] != NULL; ++sentenceIndex)
    {
        int* tokenList = _sentenceTokenLists[sentenceIndex];
 
        const char* tokensAsString = _TokensToString(tokenList);
 
        DynamicString sentence = { 0 };
        bool success = Interpreter_Interpret(tokenList, &sentence);
 
        if (success)
        {
            // 50 is a magic number corresponding to the longest token list
            // expressed as a string.  Derived empirically.  It makes the
            // output easier to, er, interpret.
            printf("  %-50s ==> \"%s\"\n", tokensAsString, sentence.string);
        }
        DynamicString_Clear(&sentence);
        if (!success)
        {
            break;
        }
    }
 
    printf("  Done.\n");
    // ! [Using Interpreter in C]
}