bshell: re-organise build into three separate components

bshell: the front-end binary
bshell.runtime: contains the parser, compiler, and classes needed to run bshell scripts
bshell.core: contains the builtin commandlets and aliases

bshell.runtime/compile/var.c

@@ -0,0 +1,54 @@
+#include "compile-node.h"
+
+enum bshell_status var_load(
+	struct compile_ctx *ctx,
+	struct compile_value *value)
+{
+	struct bshell_var_ast_node *var
+		= (struct bshell_var_ast_node *)value->v_node;
+	unsigned long index = bshell_scriptblock_get_string(
+		ctx->c_block,
+		var->n_ident->tok_str);
+	if (index == POOL_INDEX_INVALID) {
+		return BSHELL_ERR_NO_MEMORY;
+	}
+
+	bshell_scriptblock_push_instruction(
+		ctx->c_block,
+		BSHELL_OPCODE_LDLOCAL,
+		index);
+	return BSHELL_SUCCESS;
+}
+
+enum bshell_status var_store(
+	struct compile_ctx *ctx,
+	struct compile_value *value)
+{
+	struct bshell_var_ast_node *var
+		= (struct bshell_var_ast_node *)value->v_node;
+	unsigned long index = bshell_scriptblock_get_string(
+		ctx->c_block,
+		var->n_ident->tok_str);
+	if (index == POOL_INDEX_INVALID) {
+		return BSHELL_ERR_NO_MEMORY;
+	}
+
+	bshell_scriptblock_push_instruction(
+		ctx->c_block,
+		BSHELL_OPCODE_STLOCAL,
+		index);
+	return BSHELL_SUCCESS;
+}
+
+static const struct compile_value_type var_type = {
+	.v_load = var_load,
+	.v_store = var_store,
+};
+
+struct compile_result compile_var(
+	struct compile_ctx *ctx,
+	struct bshell_ast_node *src)
+{
+	compile_push_value(ctx, &var_type, src);
+	return COMPILE_OK(0);
+}