diff options
Diffstat (limited to 'src/lyn.c')
| -rw-r--r-- | src/lyn.c | 333 |
1 files changed, 328 insertions, 5 deletions
@@ -1,4 +1,5 @@ #include <errno.h> +#include <assert.h> #include <stdbool.h> #include <string.h> #include <stdio.h> @@ -6,14 +7,326 @@ #include <stdlib.h> #include <lyn/lyn.h> +#include <lyn/ast.h> #include <lyn/parser.h> #include <lyn/debug.h> +static int builtin_let(struct lyn *lyn, struct vec args) +{ + assert(vec_len(&args) == 3); + + struct lyn_value name = lyn_at(args, 1); + assert(name.kind == LYN_ID); + + struct lyn_value value = lyn_at(args, 2); + if (lyn_eval(lyn, value)) + return -1; + + value = lyn_res(lyn); + assert(value.kind == LYN_INT); + + return lyn_create_symbol(lyn, name.s, lyn_var(value)); +} + +static int builtin_set(struct lyn *lyn, struct vec args) +{ + assert(vec_len(&args) == 3); + + struct lyn_value name = lyn_at(args, 1); + assert(name.kind == LYN_ID); + + struct lyn_value value = lyn_at(args, 2); + if (lyn_eval(lyn, value)) + return -1; + + value = lyn_res(lyn); + assert(value.kind == LYN_INT); + + return lyn_replace_symbol(lyn, name.s, lyn_var(value)); +} + +static int builtin_for(struct lyn *lyn, struct vec args) +{ + assert(vec_len(&args) == 5); + + struct lyn_value init = lyn_at(args, 1); + struct lyn_value cond = lyn_at(args, 2); + struct lyn_value post = lyn_at(args, 3); + struct lyn_value body = lyn_at(args, 4); + + if (lyn_eval(lyn, init)) + return -1; + +top: + if (lyn_eval(lyn, cond)) + return -1; + + struct lyn_value check = lyn_res(lyn); + assert(check.kind == LYN_INT); + + if (check.i) { + if (lyn_eval(lyn, body)) + return -1; + + if (lyn_eval(lyn, post)) + return -1; + + goto top; + } + + return 0; +} + +static int builtin_println(struct lyn *lyn, struct vec args) +{ + assert(vec_len(&args) == 2); + + struct lyn_value value = lyn_at(args, 1); + if (lyn_eval(lyn, value)) + return -1; + + value = lyn_res(lyn); + assert(value.kind == LYN_INT); + + printf("%lld\n", value.i); + return 0; +} + +static int builtin_lt(struct lyn *lyn, struct vec args) +{ + assert(vec_len(&args) == 3); + struct lyn_value left = lyn_at(args, 1); + struct lyn_value right = lyn_at(args, 2); + + if (lyn_eval(lyn, left)) + return -1; + + left = lyn_res(lyn); + assert(left.kind == LYN_INT); + + if (lyn_eval(lyn, right)) + return -1; + + right = lyn_res(lyn); + assert(right.kind == LYN_INT); + + lyn_return(lyn, gen_int(left.i < right.i)); + return 0; +} + +static int builtin_plus(struct lyn *lyn, struct vec args) +{ + assert(vec_len(&args) == 3); + struct lyn_value left = lyn_at(args, 1); + struct lyn_value right = lyn_at(args, 2); + + if (lyn_eval(lyn, left)) + return -1; + + left = lyn_res(lyn); + assert(left.kind == LYN_INT); + + if (lyn_eval(lyn, right)) + return -1; + + right = lyn_res(lyn); + assert(right.kind == LYN_INT); + + lyn_return(lyn, gen_int(left.i + right.i)); + return 0; +} + struct lyn lyn_create() { return (struct lyn){}; } +struct visible { + const char *name; + struct lyn_symbol symb; +}; + +int lyn_create_scope(struct lyn *lyn) +{ + struct lyn_scope *scope = calloc(1, sizeof(struct lyn_scope)); + if (!scope) + return -1; + + scope->visible = vec_create(sizeof(struct visible)); + scope->parent = lyn->cur; + + if (!lyn->root) + lyn->root = scope; + + lyn->cur = scope; + return 0; +} + +static struct visible *scope_find(struct lyn_scope *scope, const char *name) +{ + foreach_vec(vi, scope->visible) { + struct visible *v = vec_at(&scope->visible, vi); + if (strcmp(v->name, name) == 0) + return v; + } + + return NULL; +} + +static struct visible *scopes_find(struct lyn_scope *scope, const char *name) +{ + while (scope) { + struct visible *v = scope_find(scope, name); + if (v) + return v; + + scope = scope->parent; + } + + return NULL; +} + +static int scope_add(struct lyn_scope *scope, const char *name, struct lyn_symbol symb) +{ + if (scope_find(scope, name)) { + error("%s exists in scope\n", name); + return -1; + } + + struct visible v = {.name = name, .symb = symb}; + vect_append(struct visible, scope->visible, &v); + return 0; +} + +int lyn_create_symbol(struct lyn *lyn, const char *name, struct lyn_symbol symb) +{ + return scope_add(lyn->cur, name, symb); +} + +struct lyn_symbol *lyn_lookup_symbol(struct lyn *lyn, const char *name) +{ + struct visible *v = scopes_find(lyn->cur, name); + if (!v) + return NULL; + + return &v->symb; +} + +int lyn_replace_symbol(struct lyn *lyn, const char *name, struct lyn_symbol symb) +{ + struct visible *v = scopes_find(lyn->cur, name); + if (!v) + return -1; + + v->symb = symb; + return 0; +} + +int lyn_init(struct lyn *lyn) +{ + if (lyn_create_scope(lyn)) + return -1; + + if (lyn_create_symbol(lyn, "let", lyn_syntax(builtin_let))) + return -1; + + if (lyn_create_symbol(lyn, "for", lyn_syntax(builtin_for))) + return -1; + + if (lyn_create_symbol(lyn, "set", lyn_syntax(builtin_set))) + return -1; + + if (lyn_create_symbol(lyn, "println", lyn_proc(builtin_println))) + return -1; + + if (lyn_create_symbol(lyn, "<", lyn_proc(builtin_lt))) + return -1; + + if (lyn_create_symbol(lyn, "+", lyn_proc(builtin_plus))) + return -1; + + return 0; +} + +static int eval_group(struct lyn *lyn, struct lyn_value group) +{ + assert(group.kind == LYN_GROUP); + foreach_vec(gi, group.args) { + struct lyn_value arg = lyn_at(group.args, gi); + if (lyn_eval(lyn, arg)) + return -1; + } + + return 0; +} + +static int eval_apply(struct lyn *lyn, struct lyn_value apply) +{ + assert(apply.kind == LYN_APPLY); + foreach_vec(ai, apply.args) { + struct lyn_value arg = lyn_at(apply.args, ai); + if (lyn_eval(lyn, arg)) + return -1; + } + + return 0; +} + +int lyn_apply_cmd(struct lyn *lyn, struct lyn_symbol *cmd, struct vec args) +{ + switch (cmd->kind) { + case LYN_BUILTIN_SYNTAX: return cmd->call(lyn, args); + case LYN_BUILTIN_PROC: return cmd->call(lyn, args); + default: abort(); + } + + return 0; +} + +static int eval_cmd(struct lyn *lyn, struct lyn_value cmd) +{ + assert(cmd.kind == LYN_CMD); + + struct lyn_value name = lyn_at(cmd.args, 0); + + /* to start with */ + struct lyn_symbol *symb = lyn_lookup_symbol(lyn, name.s); + assert(symb); + + return lyn_apply_cmd(lyn, symb, cmd.args); +} + +static int eval_int(struct lyn *lyn, struct lyn_value i) +{ + assert(i.kind == LYN_INT); + lyn_return(lyn, i); + return 0; +} + +static int eval_id(struct lyn *lyn, struct lyn_value id) +{ + assert(id.kind == LYN_ID); + struct lyn_symbol *symb = lyn_lookup_symbol(lyn, id.s); + assert(symb && symb->kind == LYN_VAR); + + lyn_return(lyn, symb->value); + return 0; +} + +int lyn_eval(struct lyn *lyn, struct lyn_value value) +{ + switch (value.kind) { + case LYN_GROUP: return eval_group(lyn, value); + case LYN_APPLY: return eval_apply(lyn, value); + case LYN_CMD: return eval_cmd(lyn, value); + case LYN_INT: return eval_int(lyn, value); + case LYN_ID: return eval_id(lyn, value); + default: error("unhandled case in interp eval"); break; + } + + return -1; +} + int lyn_eval_str(struct lyn *lyn, const char *name, const char *str) { struct parser *p = create_parser(); @@ -21,15 +334,15 @@ int lyn_eval_str(struct lyn *lyn, const char *name, const char *str) return -1; parse(p, name, str); - struct ast *ast = p->tree; + struct lyn_value ast = p->tree; bool failed = p->failed; destroy_parser(p); - if (!failed) { - ast_dump_list(0, ast); - } + if (failed) + return -1; - return failed; + ast_dump(0, ast); + return lyn_eval(lyn, ast); } /** @@ -84,6 +397,16 @@ int lyn_eval_file(struct lyn *lyn, const char *fname) return ret; } +void lyn_return(struct lyn *lyn, struct lyn_value ast) +{ + lyn->res = ast; +} + +struct lyn_value lyn_res(struct lyn *lyn) +{ + return lyn->res; +} + void lyn_destroy(struct lyn *lyn) { } |