@@ 1,6 1,7 @@ #define _POSIX_C_SOURCE 200809L
  #include <assert.h>
  #include <errno.h>
+ #include <fnmatch.h>
  #include <mrsh/buffer.h>
  #include <mrsh/parser.h>
  #include <stdio.h>


@@ 252,6 253,47 @@ return strdup(str);
  }
  
+ static char *trim_pattern(const char *str, const char *pattern, bool suffix,
+ 		bool largest) {
+ 	size_t len = strlen(str);
+ 	ssize_t begin, end, delta;
+ 	if ((!suffix && !largest) || (suffix && largest)) {
+ 		begin = 0;
+ 		end = len;
+ 		delta = 1;
+ 	} else {
+ 		begin = len - 1;
+ 		end = -1;
+ 		delta = -1;
+ 	}
+ 
+ 	char *buf = strdup(str);
+ 	for (ssize_t i = begin; i != end; i += delta) {
+ 		char ch = buf[i];
+ 		buf[i] = '\0';
+ 
+ 		const char *match, *trimmed;
+ 		if (!suffix) {
+ 			match = buf;
+ 			trimmed = str + i;
+ 		} else {
+ 			match = str + i;
+ 			trimmed = buf;
+ 		}
+ 
+ 		if (fnmatch(pattern, match, 0) == 0) {
+ 			char *result = strdup(trimmed);
+ 			free(buf);
+ 			return result;
+ 		}
+ 
+ 		buf[i] = ch;
+ 	}
+ 	free(buf);
+ 
+ 	return strdup(str);
+ }
+ 
  static int apply_parameter_str_op(struct context *ctx,
  		struct mrsh_word_parameter *wp, const char *str,
  		struct mrsh_word **result) {


@@ 286,7 328,6 @@ wp->op == MRSH_PARAM_DPERCENT;
  		bool largest = wp->op == MRSH_PARAM_DPERCENT ||
  			wp->op == MRSH_PARAM_DHASH;
- 		(void)largest;
  
  		struct mrsh_word *pattern = mrsh_word_copy(wp->arg);
  		int ret = run_word(ctx, &pattern);


@@ 294,19 335,23 @@ return ret;
  		}
  
+ 		char *result_str;
  		char *pattern_str = word_to_pattern(pattern);
  		if (pattern_str == NULL) {
  			char *arg = mrsh_word_str(pattern);
  			mrsh_word_destroy(pattern);
- 			char *result_str = trim_str(str, arg, suffix);
+ 			result_str = trim_str(str, arg, suffix);
  			free(arg);
- 			struct mrsh_word_string *result_ws =
- 				mrsh_word_string_create(result_str, false);
- 			*result = &result_ws->word;
- 			return 0;
+ 		} else {
+ 			mrsh_word_destroy(pattern);
+ 			result_str = trim_pattern(str, pattern_str, suffix, largest);
+ 			free(pattern_str);
  		}
  
- 		assert(false); // TODO
+ 		struct mrsh_word_string *result_ws =
+ 			mrsh_word_string_create(result_str, false);
+ 		*result = &result_ws->word;
+ 		return 0;
  	default:
  		assert(false);
  	}

@@ 59,14 59,14 @@ x=file.c
  echo ${x%.c}.o
  # ${parameter%%word}
- #x=posix/src/std
- #echo ${x%%/*}
+ x=posix/src/std
+ echo ${x%%/*}
  # ${parameter#word}
  x=$HOME/src/cmd
  echo ${x#$HOME}
  # ${parameter##word}
- #x=/one/two/three
- #echo ${x##*/}
+ x=/one/two/three
+ echo ${x##*/}
  
  echo ""
  echo "Command Substitution"