mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Allow [a, b, ..., c] transcription patterns in MBE.

Browse Source
This commit is contained in:
Paul Stansifer 2011-08-11 11:09:54 -07:00
parent d2f9b15052
commit 87b56b5565
2 changed files with 47 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

66
src/comp/syntax/ext/simplext.rs
View File

@ -92,19 +92,21 @@ type match_result = option::t[arb_depth[matchable]];
type selector = fn(&matchable) -> match_result ; type selector = fn(&matchable) -> match_result ;
fn elts_to_ell(cx: &ext_ctxt, elts: &[@expr]) fn elts_to_ell(cx: &ext_ctxt, elts: &[@expr])
-> {fixed: [@expr], rep: option::t[@expr]} { -> {pre: [@expr], rep: option::t[@expr], post: [@expr]} {
let idx: uint = 0u; let idx: uint = 0u;
let res = none;
for elt: @expr in elts { for elt: @expr in elts {
alt elt.node { alt elt.node {
expr_mac(m) { expr_mac(m) {
alt m.node { alt m.node {
ast::mac_ellipsis. { ast::mac_ellipsis. {
let last = ivec::len(elts) - 1u; if res != none {
if idx != last { cx.span_fatal(m.span, "only one ellipsis allowed");
cx.span_fatal(m.span, "ellipses must occur last");
} }
ret {fixed: ivec::slice(elts, 0u, last - 1u), res = some({pre: ivec::slice(elts, 0u, idx - 1u),
rep: some(elts.(last - 1u))}; rep: some(elts.(idx - 1u)),
post: ivec::slice(elts, idx + 1u,
ivec::len(elts))});
} }
_ { } _ { }
} }
@ -113,7 +115,10 @@ fn elts_to_ell(cx: &ext_ctxt, elts: &[@expr])
} }
idx += 1u; idx += 1u;
} }
ret {fixed: elts, rep: none}; ret alt res {
some(val) { val }
none. { {pre: elts, rep: none, post: ~[]} }
}
} }
fn option_flatten_map[T, U](f: &fn(&T) -> option::t[U] , v: &[T]) -> fn option_flatten_map[T, U](f: &fn(&T) -> option::t[U] , v: &[T]) ->
@ -275,8 +280,8 @@ fn transcribe_exprs(cx: &ext_ctxt, b: &bindings, idx_path: @mutable [uint],
recur: fn(&@expr) -> @expr , exprs: [@expr]) recur: fn(&@expr) -> @expr , exprs: [@expr])
-> [@expr] { -> [@expr] {
alt elts_to_ell(cx, exprs) { alt elts_to_ell(cx, exprs) {
{fixed: fixed, rep: repeat_me_maybe} { {pre: pre, rep: repeat_me_maybe, post: post} {
let res = ivec::map(recur, fixed); let res = ivec::map(recur, pre);
alt repeat_me_maybe { alt repeat_me_maybe {
none. {} none. {}
some(repeat_me) { some(repeat_me) {
@ -324,6 +329,7 @@ fn transcribe_exprs(cx: &ext_ctxt, b: &bindings, idx_path: @mutable [uint],
} }
} }
} }
res += ivec::map(recur, post);
ret res; ret res;
} }
} }
@ -440,14 +446,25 @@ fn p_t_s_rec(cx: &ext_ctxt, m: &matchable, s: &selector, b: &binders) {
expr_path(p_pth) { p_t_s_r_path(cx, p_pth, s, b); } expr_path(p_pth) { p_t_s_r_path(cx, p_pth, s, b); }
expr_vec(p_elts, _, _) { expr_vec(p_elts, _, _) {
alt elts_to_ell(cx, p_elts) { alt elts_to_ell(cx, p_elts) {
{fixed: fixed, rep: some(repeat_me)} { {pre: pre, rep: some(repeat_me), post: post} {
if(ivec::len(fixed) > 0u) { p_t_s_r_length(cx, ivec::len(pre) + ivec::len(post),
p_t_s_r_actual_vector(cx, fixed, true, s, b); true, s, b);
if(ivec::len(pre) > 0u) {
p_t_s_r_actual_vector(cx, pre, true, s, b);
}
p_t_s_r_ellipses(cx, repeat_me, ivec::len(pre), s, b);
if(ivec::len(post) > 0u) {
cx.span_unimpl(e.span,
"matching after `...` not yet supported");
} }
p_t_s_r_ellipses(cx, repeat_me, ivec::len(fixed), s, b);
} }
{fixed: fixed, rep: none.} { {pre: pre, rep: none., post: post} {
p_t_s_r_actual_vector(cx, fixed, false, s, b); if post != ~[] {
cx.bug("elts_to_ell provided an invalid result");
}
p_t_s_r_length(cx, ivec::len(pre), false, s, b);
p_t_s_r_actual_vector(cx, pre, false, s, b);
} }
} }
} }
@ -606,17 +623,17 @@ fn p_t_s_r_ellipses(cx: &ext_ctxt, repeat_me: @expr, offset: uint,
compose_sels(s, bind select(cx, repeat_me, offset, _)), b); compose_sels(s, bind select(cx, repeat_me, offset, _)), b);
} }
fn p_t_s_r_actual_vector(cx: &ext_ctxt, elts: [@expr], repeat_after: bool,
s: &selector, b: &binders) { fn p_t_s_r_length(cx: &ext_ctxt, len: uint, at_least: bool, s: selector,
fn len_select(cx: &ext_ctxt, m: &matchable, repeat_after: bool, len: uint) b: &binders) {
fn len_select(cx: &ext_ctxt, m: &matchable, at_least: bool, len: uint)
-> match_result { -> match_result {
ret alt m { ret alt m {
match_expr(e) { match_expr(e) {
alt e.node { alt e.node {
expr_vec(arg_elts, _, _) { expr_vec(arg_elts, _, _) {
let actual_len = ivec::len(arg_elts); let actual_len = ivec::len(arg_elts);
if (repeat_after && actual_len >= len) if (at_least && actual_len >= len) || actual_len == len {
|| actual_len == len {
some(leaf(match_exact)) some(leaf(match_exact))
} else { none } } else { none }
} }
@ -627,10 +644,11 @@ fn p_t_s_r_actual_vector(cx: &ext_ctxt, elts: [@expr], repeat_after: bool,
} }
} }
b.literal_ast_matchers += b.literal_ast_matchers +=
~[compose_sels(s, bind len_select(cx, _, repeat_after, ~[compose_sels(s, bind len_select(cx, _, at_least, len))];
ivec::len(elts)))]; }
fn p_t_s_r_actual_vector(cx: &ext_ctxt, elts: [@expr], repeat_after: bool,
s: &selector, b: &binders) {
let idx: uint = 0u; let idx: uint = 0u;
while idx < ivec::len(elts) { while idx < ivec::len(elts) {
fn select(cx: &ext_ctxt, m: &matchable, idx: uint) -> match_result { fn select(cx: &ext_ctxt, m: &matchable, idx: uint) -> match_result {
@ -678,7 +696,7 @@ fn add_new_extension(cx: &ext_ctxt, sp: span, arg: @expr,
alt mac.node { alt mac.node {
mac_invoc(pth, invoc_arg, body) { mac_invoc(pth, invoc_arg, body) {
alt path_to_ident(pth) { alt path_to_ident(pth) {
some(id) { some(id) {
alt macro_name { alt macro_name {
none. { macro_name = some(id); } none. { macro_name = some(id); }
some(other_id) { some(other_id) {

5
src/test/run-pass/macro-by-example-2.rs
View File

@ -43,4 +43,9 @@ fn main() {
assert (#transcr_mixed[10, 5, 4, 3, 2, 1] == 210); assert (#transcr_mixed[10, 5, 4, 3, 2, 1] == 210);
#macro[[#surround[pre, [xs, ...], post],
[pre, xs, ..., post]]];
assert (#surround[1, [2,3,4], 5] == [1,2,3,4,5]);
} }