diff options
Diffstat (limited to 'compiler')
| -rw-r--r-- | compiler/compile.c | 144 |
1 files changed, 134 insertions, 10 deletions
diff --git a/compiler/compile.c b/compiler/compile.c index 5c88b97..eab1b3c 100644 --- a/compiler/compile.c +++ b/compiler/compile.c @@ -1162,7 +1162,7 @@ static bool path_append(Compiler *c, Stmt *s, const Token *name) { } /* , b, c = x, y, z after the first name: every name, then as many values on the line. */ -static void several(Compiler *c, Stmt *s, const char *first) { +static void several_names(Compiler *c, Stmt *s, const char *first) { s->names = allocate(c, STACK * sizeof(*s->names)); memcpy(s->names[s->name_count++], first, NAME); while (is(c, ",")) { @@ -1174,6 +1174,10 @@ static void several(Compiler *c, Stmt *s, const char *first) { if (!strcmp(s->names[i], name.text)) fail_at(c, name.line, name.column, "'%s' is named twice", name.text); memcpy(s->names[s->name_count++], name.text, NAME); } +} + +/* = x, y (after the names): every name's value, or one call that gives them all. */ +static void several_values(Compiler *c, Stmt *s) { expect(c, "=", "'='"); Expr **tail = &s->value; unsigned values = 0; @@ -1189,6 +1193,99 @@ static void several(Compiler *c, Stmt *s, const char *first) { fail_at(c, s->line, s->column, "%u names take %u values, not %u", s->name_count, s->name_count, values); } +/* A target of a, xs[i].x = ...: a name (S_ASSIGN), a list's item's field or its item at a position (S_SET), or an + * index's field (at.x, S_SET); its value comes later. */ +static Stmt *target(Compiler *c, Token name) { + Stmt *t = allocate(c, sizeof(*t)); + t->line = name.line, t->column = name.column; + memcpy(t->name, name.text, NAME); + if (is(c, "[")) { + take(c); + t->kind = S_SET; + t->first = expression(c, 0, true); + newlines(c); + expect(c, "]", "']'"); + if (is(c, ".")) { + take(c); + Token field = expect_name(c, "a field"); + memcpy(t->member, field.text, NAME); + } + return t; + } + if (is(c, ".")) { + take(c); + Token field = expect_name(c, "a field"); + t->kind = S_SET; + t->first = node(c, E_NAME, name.line, name.column); + memcpy(t->first->name, name.text, NAME); + t->name[0] = 0; + memcpy(t->member, field.text, NAME); + return t; + } + if (reserved_name(name.text)) fail_at(c, name.line, name.column, "'%s' is reserved", name.text); + t->kind = S_ASSIGN; + return t; +} + +/* a, xs[i].x = x, y after its first target: every target its value at once, the values first, in order. Names alone + * are S_ASSIGNS; with a field or an item among them, the values go to lets of their own first (a literal, which + * reads nothing, goes straight), then each target takes its own: a let each and a statement each, linked. */ +static Stmt *together(Compiler *c, Stmt *first) { + Stmt *targets[STACK]; + unsigned n = 0; + bool names = first->kind == S_ASSIGN; + targets[n++] = first; + while (is(c, ",")) { + take(c); + Token name = expect_name(c, "a name"); + if (n == STACK) fail_at(c, name.line, name.column, "at most %d names take values at once", STACK); + Stmt *t = target(c, name); + for (unsigned i = 0; t->kind == S_ASSIGN && i < n; ++i) + if (targets[i]->kind == S_ASSIGN && !strcmp(targets[i]->name, t->name)) + fail_at(c, name.line, name.column, "'%s' is named twice", name.text); + names = names && t->kind == S_ASSIGN; + targets[n++] = t; + } + Stmt *s = allocate(c, sizeof(*s)); + s->line = first->line, s->column = first->column; + s->names = allocate(c, STACK * sizeof(*s->names)); + s->name_count = n; + for (unsigned i = 0; i < n; ++i) + if (names) memcpy(s->names[i], targets[i]->name, NAME); + else snprintf(s->names[i], NAME, ".%d.%d.%u", s->line, s->column, i); /* no name of the source's */ + s->kind = names ? S_ASSIGNS : S_LETS; + several_values(c, s); + if (names) return s; + Expr *values[STACK]; + unsigned count = 0; + for (Expr *v = s->value; v; v = v->next) values[count++] = v; + Stmt *last = s; + Expr **link = &s->value; + unsigned kept = 0; + for (unsigned i = 0; i < n; ++i) { + Expr *v = count == n ? values[i] : NULL; /* NULL: one call gives them all */ + if (v && (v->kind == E_NUMBER || v->kind == E_BOOL || v->kind == E_TEXT)) { + v->next = NULL; /* a literal reads nothing: straight to its target */ + targets[i]->value = v; + } else { + memcpy(s->names[kept++], s->names[i], NAME); + Expr *given = node(c, E_NAME, s->line, s->column); + memcpy(given->name, s->names[i], NAME); + targets[i]->value = given; + if (v) *link = v, link = &v->next; + } + last = last->next = targets[i]; + } + if (count == n) *link = NULL; + s->name_count = kept; + if (kept == 1) { /* one let: as let x = value */ + s->kind = S_LET; + memcpy(s->name, s->names[0], NAME); + s->names = NULL, s->name_count = 0; + } + return kept ? s : s->next; /* every value a literal: no lets */ +} + static Stmt *statement(Compiler *c, unsigned depth) { Token token = expect_name(c, "a statement or '}'"); Stmt *s = allocate(c, sizeof(*s)); @@ -1219,10 +1316,13 @@ static Stmt *statement(Compiler *c, unsigned depth) { memcpy(s->name, name.text, NAME); s->line = name.line; s->column = name.column; - if (is(c, ",")) { /* let a, b = x, y */ - s->kind = S_LETS; - several(c, s, name.text); - return s; + if (is(c, ",")) { /* let a, b = x, y, or let a, b: list of R (a list each, empty as it begins) */ + several_names(c, s, name.text); + if (!is(c, ":")) { + s->kind = S_LETS; + several_values(c, s); + return s; + } } if (is(c, ":")) { /* let name: list of R [by field]: the event's list, empty as it begins */ take(c); @@ -1239,6 +1339,20 @@ static Stmt *statement(Compiler *c, unsigned depth) { s->key_column = key.column; } s->listed = true; + if (s->name_count > 1) { /* the names after the first: lets of their own, of the same list, after it */ + Stmt *last = s; + for (unsigned i = 1; i < s->name_count; ++i) { + Stmt *other = allocate(c, sizeof(*other)); + *other = *s; + other->names = NULL, other->name_count = 0; + memcpy(other->name, s->names[i], NAME); + last = last->next = other; + } + s->names = NULL, s->name_count = 0; + if (is(c, "=")) + fail_at(c, c->token.line, c->token.column, "lists declared together begin empty: give each its elements apart"); + return s; + } if (is(c, "=")) { /* = [a, b, ...]: what it holds as it begins, appended in order */ take(c); Token open = expect(c, "[", "'[' and the list's elements"); @@ -1435,6 +1549,9 @@ static Stmt *statement(Compiler *c, unsigned depth) { } if (is(c, "(")) fail_at(c, field.line, field.column, "a field changes by '=', as in %s[at].%s = value", s->name, field.text); memcpy(s->member, field.text, NAME); + if (is(c, ",")) return together(c, s); /* xs[i].x, xs[i].y = a, b */ + } else if (is(c, ",")) { + return together(c, s); /* xs[i], ys[j] = a, b */ } else if (is(c, "=")) { /* tasks[at] = Task { ... }: every field of the item (no member); xs[i] = 5 */ take(c); s->value = inserted_value(c, false); @@ -1450,6 +1567,14 @@ static Stmt *statement(Compiler *c, unsigned depth) { if (is(c, ".")) { take(c); Token method = expect_name(c, "insert, remove, append or a field"); + if (is(c, ",")) { /* at.x, at.y = a, b */ + s->kind = S_SET; + s->first = node(c, E_NAME, token.line, token.column); + memcpy(s->first->name, s->name, NAME); + s->name[0] = 0; + memcpy(s->member, method.text, NAME); + return together(c, s); + } if (is(c, "=")) { /* at.field = value: a field of the item an index names. */ take(c); @@ -1488,10 +1613,9 @@ static Stmt *statement(Compiler *c, unsigned depth) { expect(c, ")", "')'"); return s; } - if (is(c, ",")) { /* a, b = b, a */ - s->kind = S_ASSIGNS; - several(c, s, token.text); - return s; + if (is(c, ",")) { /* a, b = b, a; a, xs[i].x = 1, 2 */ + s->kind = S_ASSIGN; + return together(c, s); } s->kind = S_ASSIGN; expect(c, "=", "'='"); @@ -1508,7 +1632,7 @@ static Stmt *block(Compiler *c, unsigned depth) { while (!is(c, "}")) { if (c->token.kind == T_EOF) fail_at(c, c->token.line, c->token.column, "expected '}'"); *tail = statement(c, depth); - tail = &(*tail)->next; + while (*tail) tail = &(*tail)->next; /* let a, b: list of R is a let each */ end(c); } take(c); |