frontend: split interactive and non-interactive modes into separate commands

frontend/cmd/repl.c

@@ -1,3 +1,66 @@
+#include "../debug.h"
+#include "../line-ed/line-ed.h"
 #include "cmd.h"
 
 #include <blue/cmd.h>
+#include <blue/term.h>
+#include <ivy/lang/lex.h>
+#include <stdbool.h>
+
+int repl(const b_command *cmd, const b_arglist *args, const b_array *_)
+{
+	char buf[1024];
+	struct line_ed *ed = line_ed_create();
+	struct ivy_lexer *lex;
+	enum ivy_status status = ivy_lexer_create(&lex);
+
+	if (status != IVY_OK) {
+		line_ed_destroy(ed);
+		return -1;
+	}
+
+	ivy_lexer_set_source(lex, &ed->l_line_source);
+
+	while (true) {
+		struct ivy_token *tok = ivy_lexer_read(lex);
+		status = ivy_lexer_get_status(lex);
+		if (status == IVY_ERR_EOF) {
+			break;
+		}
+
+		if (status != IVY_OK) {
+			b_err("lex error (%s)",
+			      ivy_status_to_string(ivy_lexer_get_status(lex)));
+			break;
+		}
+
+		print_lex_token(tok);
+#if 0
+		long v = line_ed_readline(ed, buf, sizeof buf);
+		if (v == -1) {
+			break;
+		}
+
+		if (v == 0) {
+			continue;
+		}
+
+		buf[strcspn(buf, "\n")] = 0;
+
+		printf("input: '%s'\n", buf);
+#endif
+	}
+
+	ivy_lexer_destroy(lex);
+	line_ed_destroy(ed);
+	return 0;
+}
+
+B_COMMAND(CMD_REPL, CMD_ROOT)
+{
+	B_COMMAND_NAME("shell");
+	B_COMMAND_SHORT_NAME('S');
+	B_COMMAND_DESC("start an interactive Ivy shell.");
+	B_COMMAND_HELP_OPTION();
+	B_COMMAND_FUNCTION(repl);
+}