commit 64eed54f29d03bca8edf361748357bd035000c40
parent 1aa7a3246a6cb0acb36928f65bcaa1a800c9f291
Author: Miccah Castorina <contact@miccah.io>
Date: Mon, 13 Dec 2021 12:22:53 -0600
strings::iter: Make riter use next to go forward
This is accomplished by adding a next and prev function pointer to the
iter struct. This means the iterator abstracts the direction from the
underlying decoder.
Signed-off-by: Miccah Castorina <contact@miccah.io>
Diffstat:
3 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/fnmatch/fnmatch.ha b/fnmatch/fnmatch.ha
@@ -165,13 +165,13 @@ fn fnmatch_internal(
let s_copy = s;
s = strings::riter(string);
for (let i = 0z; i < cnt; i += 1) {
- strings::prev(&s);
+ strings::next(&s);
};
// match the tail
let s_last = s;
for (true) {
- let rn = strings::next(&s);
+ let rn = strings::prev(&s);
let matches = match (pat_next(&p, fl)?) {
case end =>
if (rn is void) {
diff --git a/strings/iter.ha b/strings/iter.ha
@@ -4,12 +4,16 @@ use encoding::utf8;
export type iterator = struct {
dec: utf8::decoder,
push: (rune | void),
+ next: *fn(_: *utf8::decoder) (rune | void | utf8::more | utf8::invalid),
+ prev: *fn(_: *utf8::decoder) (rune | void | utf8::more | utf8::invalid),
};
// Initializes a string iterator, starting at the beginning of the string.
export fn iter(src: str) iterator = iterator {
dec = utf8::decode(src),
push = void,
+ next = &utf8::next,
+ prev = &utf8::prev,
};
// Initializes a string iterator, starting at the end of the string.
@@ -17,6 +21,8 @@ export fn riter(src: str) iterator = {
let ret = iterator {
dec = utf8::decode(src),
push = void,
+ next = &utf8::prev,
+ prev = &utf8::next,
};
ret.dec.offs = len(src);
return ret;
@@ -36,7 +42,7 @@ export fn next(iter: *iterator) (rune | void) = {
return r;
case void => void;
};
- return match (utf8::next(&iter.dec)) {
+ return match (iter.next(&iter.dec)) {
case void => void;
case (utf8::more | utf8::invalid) =>
abort("Invalid UTF-8 string (this should not happen)");
@@ -49,7 +55,7 @@ export fn next(iter: *iterator) (rune | void) = {
// string.
export fn prev(iter: *iterator) (rune | void) = {
assert(iter.push is void);
- return match (utf8::prev(&iter.dec)) {
+ return match (iter.prev(&iter.dec)) {
case void =>
yield void;
case (utf8::more | utf8::invalid) =>
@@ -107,15 +113,15 @@ export fn iter_str(iter: *iterator) str = {
s = riter("にちは");
const expected3 = ['は', 'ち', 'に'];
for (let i = 0z; i< len(expected3); i += 1) {
- match (prev(&s)) {
+ match (next(&s)) {
case let r: rune =>
assert(r == expected3[i]);
case void =>
abort();
};
};
- assert(prev(&s) is void);
- assert(next(&s) as rune == 'に');
+ assert(next(&s) is void);
+ assert(prev(&s) as rune == 'に');
};
// Returns a slice of runes for a string in O(n). The caller must free the
diff --git a/strings/trim.ha b/strings/trim.ha
@@ -41,7 +41,7 @@ export fn rtrim(input: str, trim: rune...) str = {
};
let it = riter(input);
for (true) {
- const r = match (prev(&it)) {
+ const r = match (next(&it)) {
case let r: rune =>
yield r;
case void =>
@@ -55,7 +55,7 @@ export fn rtrim(input: str, trim: rune...) str = {
};
};
if (!found) {
- next(&it);
+ prev(&it);
break;
};
};
