Task: Yahoo! search interface
C: 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <curl/curl.h>
#include "wren.h"

struct MemoryStruct {
    char *memory;
    size_t size;
};



static size_t WriteMemoryCallback(void *contents, size_t size, size_t nmemb, void *userp) {
    size_t realsize = size * nmemb;
    struct MemoryStruct *mem = (struct MemoryStruct *)userp;
 
    char *ptr = realloc(mem->memory, mem->size + realsize + 1);
    if(!ptr) {
        
        printf("not enough memory (realloc returned NULL)\n");
        return 0;
    }

    mem->memory = ptr;
    memcpy(&(mem->memory[mem->size]), contents, realsize);
    mem->size += realsize;
    mem->memory[mem->size] = 0;
    return realsize;
}

void C_bufferAllocate(WrenVM* vm) {
    struct MemoryStruct *ms = (struct MemoryStruct *)wrenSetSlotNewForeign(vm, 0, 0, sizeof(struct MemoryStruct));
    ms->memory = malloc(1);
    ms->size = 0;
}

void C_bufferFinalize(void* data) {
    struct MemoryStruct *ms = (struct MemoryStruct *)data;
    free(ms->memory);
}

void C_curlAllocate(WrenVM* vm) {
    CURL** pcurl = (CURL**)wrenSetSlotNewForeign(vm, 0, 0, sizeof(CURL*));
    *pcurl = curl_easy_init();
}

void C_value(WrenVM* vm) {
    struct MemoryStruct *ms = (struct MemoryStruct *)wrenGetSlotForeign(vm, 0);
    wrenSetSlotString(vm, 0, ms->memory);
}

void C_easyPerform(WrenVM* vm) {
    CURL* curl = *(CURL**)wrenGetSlotForeign(vm, 0);
    curl_easy_perform(curl);
}

void C_easyCleanup(WrenVM* vm) {
    CURL* curl = *(CURL**)wrenGetSlotForeign(vm, 0);
    curl_easy_cleanup(curl);
}

void C_easySetOpt(WrenVM* vm) {
    CURL* curl = *(CURL**)wrenGetSlotForeign(vm, 0);
    CURLoption opt = (CURLoption)wrenGetSlotDouble(vm, 1);
    if (opt < 10000) {
        long lparam = (long)wrenGetSlotDouble(vm, 2);
        curl_easy_setopt(curl, opt, lparam);
    } else if (opt < 20000) {
        if (opt == CURLOPT_WRITEDATA) {
            struct MemoryStruct *ms = (struct MemoryStruct *)wrenGetSlotForeign(vm, 2);
            curl_easy_setopt(curl, opt, (void *)ms);
        } else if (opt == CURLOPT_URL) {
            const char *url = wrenGetSlotString(vm, 2);
            curl_easy_setopt(curl, opt, url);
        }
    } else if (opt < 30000) {
        if (opt == CURLOPT_WRITEFUNCTION) {
            curl_easy_setopt(curl, opt, &WriteMemoryCallback);
        }
    }
}

WrenForeignClassMethods bindForeignClass(WrenVM* vm, const char* module, const char* className) {
    WrenForeignClassMethods methods;
    methods.allocate = NULL;
    methods.finalize = NULL;
    if (strcmp(module, "main") == 0) {
        if (strcmp(className, "Buffer") == 0) {
            methods.allocate = C_bufferAllocate;
            methods.finalize = C_bufferFinalize;
        } else if (strcmp(className, "Curl") == 0) {
            methods.allocate = C_curlAllocate;
        }
    }
    return methods;
}

WrenForeignMethodFn bindForeignMethod(
    WrenVM* vm,
    const char* module,
    const char* className,
    bool isStatic,
    const char* signature) {
    if (strcmp(module, "main") == 0) {
        if (strcmp(className, "Buffer") == 0) {
            if (!isStatic && strcmp(signature, "value") == 0)           return C_value;
        } else if (strcmp(className, "Curl") == 0) {
            if (!isStatic && strcmp(signature, "easySetOpt(_,_)") == 0) return C_easySetOpt;
            if (!isStatic && strcmp(signature, "easyPerform()") == 0)   return C_easyPerform;
            if (!isStatic && strcmp(signature, "easyCleanup()") == 0)   return C_easyCleanup;
        }
    }
    return NULL;
}

static void writeFn(WrenVM* vm, const char* text) {
    printf("%s", text);
}

void errorFn(WrenVM* vm, WrenErrorType errorType, const char* module, const int line, const char* msg) {
    switch (errorType) {
        case WREN_ERROR_COMPILE:
            printf("[%s line %d] [Error] %s\n", module, line, msg);
            break;
        case WREN_ERROR_STACK_TRACE:
            printf("[%s line %d] in %s\n", module, line, msg);
            break;
        case WREN_ERROR_RUNTIME:
            printf("[Runtime Error] %s\n", msg);
            break;
    }
}

char *readFile(const char *fileName) {
    FILE *f = fopen(fileName, "r");
    fseek(f, 0, SEEK_END);
    long fsize = ftell(f);
    rewind(f);
    char *script = malloc(fsize + 1);
    fread(script, 1, fsize, f);
    fclose(f);
    script[fsize] = 0;
    return script;
}

static void loadModuleComplete(WrenVM* vm, const char* module, WrenLoadModuleResult result) {
    if( result.source) free((void*)result.source);
}

WrenLoadModuleResult loadModule(WrenVM* vm, const char* name) {
    WrenLoadModuleResult result = {0};
    if (strcmp(name, "random") != 0 && strcmp(name, "meta") != 0) {
        result.onComplete = loadModuleComplete;
        char fullName[strlen(name) + 6];
        strcpy(fullName, name);
        strcat(fullName, ".wren");
        result.source = readFile(fullName);
    }
    return result;
}

int main(int argc, char **argv) {
    WrenConfiguration config;
    wrenInitConfiguration(&config);
    config.writeFn = &writeFn;
    config.errorFn = &errorFn;
    config.bindForeignClassFn = &bindForeignClass;
    config.bindForeignMethodFn = &bindForeignMethod;
    config.loadModuleFn = &loadModule;
    WrenVM* vm = wrenNewVM(&config);
    const char* module = "main";
    const char* fileName = "yahoo_search_interface.wren";
    char *script = readFile(fileName);
    WrenInterpretResult result = wrenInterpret(vm, module, script);
    switch (result) {
        case WREN_RESULT_COMPILE_ERROR:
            printf("Compile Error!\n");
            break;
        case WREN_RESULT_RUNTIME_ERROR:
            printf("Runtime Error!\n");
            break;
        case WREN_RESULT_SUCCESS:
            break;
    }
    wrenFreeVM(vm);
    free(script);
    return 0;
}

Java: import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

class YahooSearch {
    private String query;
    
    private int page = 1;
    
    private static final Pattern pattern = Pattern.compile(
        "<a class=\"yschttl spt\" href=\"[^*]+?\\*\\*([^\"]+?)\">(.+?)</a></h3>.*?<div class=\"(?:sm-abs|abstr)\">(.+?)</div>");

    public YahooSearch(String query) {
        this.query = query;
    }

    public List<YahooResult> search() throws MalformedURLException, URISyntaxException, IOException {
        
        
        StringBuilder searchUrl = new StringBuilder("http:
        searchUrl.append("p=").append(URLEncoder.encode(query, "UTF-8"));
        if (page > 1) {searchUrl.append("&b=").append((page - 1) * 10 + 1);}
        
        URL url = new URL(searchUrl.toString());
        List<YahooResult> result = new ArrayList<YahooResult>();
        StringBuilder sb = new StringBuilder();
        
        BufferedReader in = null;
        try {
            in = new BufferedReader(new InputStreamReader(url.openStream()));
            
            String line = in.readLine();
            while (line != null) {
                sb.append(line);
                line = in.readLine();
            }
        }
        catch (IOException ioe) {
            ioe.printStackTrace();
        }
        finally {
            try {in.close();} catch (Exception ignoreMe) {}
        }
        String searchResult = sb.toString();
        
        Matcher matcher = pattern.matcher(searchResult);
        while (matcher.find()) {
            
            String resultUrl = URLDecoder.decode(matcher.group(1), "UTF-8");
            String resultTitle = matcher.group(2).replaceAll("</?b>", "").replaceAll("<wbr ?/?>", "");
            String resultContent = matcher.group(3).replaceAll("</?b>", "").replaceAll("<wbr ?/?>", "");
            
            result.add(new YahooResult(resultUrl, resultTitle, resultContent));
        }
        return result;
    }

    public List<YahooResult> search(int page) throws MalformedURLException, URISyntaxException, IOException {
        
        this.page = page;
        return search();
    }

    public List<YahooResult> nextPage() throws MalformedURLException, URISyntaxException, IOException {
        
        page++;
        return search();
    }

    public List<YahooResult> previousPage() throws MalformedURLException, URISyntaxException, IOException {
        
        if (page > 1) {
            page--;
            return search();
        } else return new ArrayList<YahooResult>();
    }
}

class YahooResult {
    private URL url;
    private String title;
    private String content;

    public URL getUrl() {
        return url;
    }

    public void setUrl(URL url) {
        this.url = url;
    }

    public void setUrl(String url) throws MalformedURLException {
        this.url = new URL(url);
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }

    public YahooResult(URL url, String title, String content) {
        setUrl(url);
        setTitle(title);
        setContent(content);
    }

    public YahooResult(String url, String title, String content) throws MalformedURLException {
        setUrl(url);
        setTitle(title);
        setContent(content);
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        if (title != null) {
            sb.append(",title=").append(title);
        }
        if (url != null) {
            sb.append(",url=").append(url);
        }
        return sb.charAt(0) == ',' ? sb.substring(1) : sb.toString();
    }
}

public class TestYahooSearch {
    public static void main(String[] args) throws MalformedURLException, URISyntaxException, IOException {
        
        YahooSearch search = new YahooSearch("Rosetta code");
        
        List<YahooResult> results = search.search();
        
        for (YahooResult result : results) {
            System.out.println(result.toString());
        }
    }
}