AutotoolsDeps and environment access

reference/conanfile/tools/env/environment.rst

@@ -1,3 +1,5 @@
+.. _conan_tools_env_environment:
+
 Environment
 ===========
 
@@ -20,8 +22,10 @@ It allows different operations like:
     env.define("MYVAR1", "MyValue1")  # Overwrite previously existing MYVAR1 with new value
     env.append("MYVAR2", "MyValue2")  # Append to existing MYVAR2 the new value
     env.prepend("MYVAR3", "MyValue3") # Prepend to existing MYVAR3 the new value
+    env.remove("MYVAR3", "MyValue3")  # Remove the MyValue3 from MYVAR3
     env.unset("MYVAR4")               # Remove MYVAR4 definition from environment
 
+
     # And the equivalent with paths
     env.define_path("MYPATH1", "path/one")  # Overwrite previously existing MYPATH1 with new value
     env.append_path("MYPATH2", "path/two")  # Append to existing MYPATH2 the new value
@@ -78,6 +82,18 @@ Environments can be applied in the python environment:
        ...
 
 
+You can iterate an Environment object:
+
+.. code:: python
+
+    env1 = Environment()
+    env1.append("foo", "var")
+    env1.append("foo", "var2")
+    for name, value in env.items():
+        assert name == "foo":
+        assert value == "var var2"
+
+
 There are some places where this ``Environment`` is used:
 
 - In recipes ``package_info()`` method, in new ``self.buildenv_info`` and ``self.runenv_info``.

reference/conanfile/tools/gnu/autotoolsdeps.rst

@@ -55,4 +55,21 @@ At this moment, only the ``requires`` information is generated, the ``build_requ
 Attributes
 ++++++++++
 
-At this moment, it is pending to expose attributes to let the user modify the behavior before calling ``generate()``
+* **environment** : :ref:`Environment<conan_tools_env_environment>` object containing the computed variables. If you need
+  to modify some of the computed values you can access to the ``environment`` object.
+
+.. code:: python
+
+    from conans import ConanFile
+    from conan.tools.gnu import AutotoolsDeps
+
+    class App(ConanFile):
+        settings = "os", "arch", "compiler", "build_type"
+
+        def generate(self):
+            tc = AutotoolsDeps(self)
+            tc.environment.remove("CPPFLAGS", "undesired_value")
+            tc.environment.append("CPPFLAGS", "var")
+            tc.environment.define("OTHER", "cat")
+            tc.environment.unset("LDFLAGS")
+            tc.generate()