Update buildexe_immediate_example.rst

Author: coder137

docs/source/getting_started/buildexe_immediate_example.rst

@@ -1,2 +1,47 @@
 BuildExe "Immediate" example
 =============================
+
+Basic Procedure
+----------------
+
+BuildExe has an "immediate" mode where it can directly provide us the Target (singular) without going through the intermediate steps that we followed in the "script" mode.
+
+.. uml::
+
+    usecase "main.cpp" as main_cpp
+    usecase "compile.toml" as compile_toml
+    usecase "host_or_cross_toolchain.toml" as host_or_cross_toolchain
+
+    rectangle "./buildexe" as buildexe_exe
+    artifact "./hello_world" as hello_world_exe
+
+    main_cpp -right-> buildexe_exe
+    compile_toml -up-> buildexe_exe
+    host_or_cross_toolchain -up-> buildexe_exe
+    buildexe_exe -right-> hello_world_exe
+
+
+What is the point of the "script" mode then?
+++++++++++++++++++++++++++++++++++++++++++++
+
+The "immediate" mode has a lot of limitations but it is also useful in certain scenarios
+
+**Limitations**
+
+* Cannot build more than one target at a time
+* No customizability allowed.
+   * Which means that apart from just building the target you cannot do anything else. 
+   * For example: Setting dependencies between targets, running custom generators, running static analysis tools and so on.
+
+**Usecase**
+
+* Simple way to build one target.
+* Completely run time dependent. Change your ``build.toml`` file and you can build a new target.
+* Very easy to know how a particular target is built. 
+   * For example. In a large project it might be very hard to visualize how a single target is built due to various code generation and library / target dependencies.
+   * Since .toml is easily readable, we can understand the sources, search directories and flags that the target requires at a glance.
+* Can be shipped to customers for a pain free build process i.e removes technical debt.
+   * Building your artifact is as simple as ``buildexe --config build.toml --config %BUILDCC_HOME/host/host_or_cross_toolchain.toml``
+   * build.toml contains the target information.
+   * host_or_cross_toolchain.toml contains the host/cross toolchain information
+   * We can combine the two into one .toml file.