From 479c245190ab69dcc8b90787eae031556e057a0a Mon Sep 17 00:00:00 2001
From: q66 <daniel@octaforge.org>
Date: Wed, 17 Aug 2016 23:54:57 +0100
Subject: [PATCH] safe typecasting accessors for Ident

---
 cubescript.cc | 109 ++++++++++++++++++++++++++++++++++++++++++++++++++
 cubescript.hh |  43 +++++++++++---------
 2 files changed, 133 insertions(+), 19 deletions(-)

diff --git a/cubescript.cc b/cubescript.cc
index 676300a1..4aae9955 100644
--- a/cubescript.cc
+++ b/cubescript.cc
@@ -124,6 +124,115 @@ Command::Command(
     name = n;
 }
 
+bool Ident::is_alias() const {
+    return get_type() == IdentType::alias;
+}
+
+Alias *Ident::get_alias() {
+    if (!is_alias()) {
+        return nullptr;
+    }
+    return static_cast<Alias *>(this);
+}
+
+Alias const *Ident::get_alias() const {
+    if (!is_alias()) {
+        return nullptr;
+    }
+    return static_cast<Alias const *>(this);
+}
+
+bool Ident::is_command() const {
+    return get_type() == IdentType::command;
+}
+
+Command *Ident::get_command() {
+    if (!is_command()) {
+        return nullptr;
+    }
+    return static_cast<Command *>(this);
+}
+
+Command const *Ident::get_command() const {
+    if (!is_command()) {
+        return nullptr;
+    }
+    return static_cast<Command const *>(this);
+}
+
+bool Ident::is_var() const {
+    IdentType tp = get_type();
+    return (tp >= IdentType::ivar) && (tp <= IdentType::svar);
+}
+
+Var *Ident::get_var() {
+    if (!is_var()) {
+        return nullptr;
+    }
+    return static_cast<Var *>(this);
+}
+
+Var const *Ident::get_var() const {
+    if (!is_var()) {
+        return nullptr;
+    }
+    return static_cast<Var const *>(this);
+}
+
+bool Ident::is_ivar() const {
+    return get_type() == IdentType::ivar;
+}
+
+Ivar *Ident::get_ivar() {
+    if (!is_ivar()) {
+        return nullptr;
+    }
+    return static_cast<Ivar *>(this);
+}
+
+Ivar const *Ident::get_ivar() const {
+    if (!is_ivar()) {
+        return nullptr;
+    }
+    return static_cast<Ivar const *>(this);
+}
+
+bool Ident::is_fvar() const {
+    return get_type() == IdentType::fvar;
+}
+
+Fvar *Ident::get_fvar() {
+    if (!is_fvar()) {
+        return nullptr;
+    }
+    return static_cast<Fvar *>(this);
+}
+
+Fvar const *Ident::get_fvar() const {
+    if (!is_fvar()) {
+        return nullptr;
+    }
+    return static_cast<Fvar const *>(this);
+}
+
+bool Ident::is_svar() const {
+    return get_type() == IdentType::svar;
+}
+
+Svar *Ident::get_svar() {
+    if (!is_svar()) {
+        return nullptr;
+    }
+    return static_cast<Svar *>(this);
+}
+
+Svar const *Ident::get_svar() const {
+    if (!is_svar()) {
+        return nullptr;
+    }
+    return static_cast<Svar const *>(this);
+}
+
 void cs_init_lib_base(CsState &cs);
 
 CsState::CsState() {
diff --git a/cubescript.hh b/cubescript.hh
index 5421bc58..de000d69 100644
--- a/cubescript.hh
+++ b/cubescript.hh
@@ -171,6 +171,12 @@ enum class IdentType {
     ivar, fvar, svar, command, alias
 };
 
+struct Command;
+struct Var;
+struct Ivar;
+struct Fvar;
+struct Svar;
+
 struct OSTD_EXPORT Ident {
     ostd::byte type; /* ID_something */
     ostd::ushort flags;
@@ -179,30 +185,29 @@ struct OSTD_EXPORT Ident {
 
     IdentType get_type() const;
 
-    bool is_alias() const {
-        return get_type() == IdentType::alias;
-    }
+    bool is_alias() const;
+    Alias *get_alias();
+    Alias const *get_alias() const;
 
-    bool is_command() const {
-        return get_type() == IdentType::command;
-    }
+    bool is_command() const;
+    Command *get_command();
+    Command const *get_command() const;
 
-    bool is_var() const {
-        IdentType tp = get_type();
-        return (tp >= IdentType::ivar) && (tp <= IdentType::svar);
-    }
+    bool is_var() const;
+    Var *get_var();
+    Var const *get_var() const;
 
-    bool is_ivar() const {
-        return get_type() == IdentType::ivar;
-    }
+    bool is_ivar() const;
+    Ivar *get_ivar();
+    Ivar const *get_ivar() const;
 
-    bool is_fvar() const {
-        return get_type() == IdentType::fvar;
-    }
+    bool is_fvar() const;
+    Fvar *get_fvar();
+    Fvar const *get_fvar() const;
 
-    bool is_svar() const {
-        return get_type() == IdentType::svar;
-    }
+    bool is_svar() const;
+    Svar *get_svar();
+    Svar const *get_svar() const;
 
 protected:
     Ident();