All references of master to main.

.github/workflows/build-live-version.yml

@@ -2,17 +2,17 @@ name: Build Live Version
 
 on:
   pull_request:
-    branches: [ master ]
+    branches: [ main ]
 
 jobs:
   build:
-    
+
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2
         with:
           persist-credentials: false
-      
+
       - uses: actions/setup-python@v2
 
       - name: Install dependencies

CODE_OF_CONDUCT.md

@@ -1,7 +1,7 @@
 <!-- Copyright Contributors to the Qiskit project. -->
 
 # Code of Conduct
-All members of this project agree to adhere to the Qiskit Code of Conduct listed at [https://github.com/Qiskit/qiskit/blob/master/CODE_OF_CONDUCT.md](https://github.com/Qiskit/qiskit/blob/master/CODE_OF_CONDUCT.md)
+All members of this project agree to adhere to the Qiskit Code of Conduct listed at [https://github.com/Qiskit/qiskit/blob/main/CODE_OF_CONDUCT.md](https://github.com/Qiskit/qiskit/blob/main/CODE_OF_CONDUCT.md)
 
 ----
 

CONTRIBUTING.md

@@ -6,7 +6,7 @@ You can contribute in many ways to this project.
 
 ## Issue reporting
 
-:fire: This is a good point to start, when you find a problem please add it to the [issue tracker](https://github.com/Qiskit/openqasm/issues). Please, use [this template](https://github.com/Qiskit/openqasm/contributing/blob/master/templates/issue.md) to add them.
+:fire: This is a good point to start, when you find a problem please add it to the [issue tracker](https://github.com/Qiskit/openqasm/issues). Please, use [this template](https://github.com/Qiskit/openqasm/contributing/blob/main/templates/issue.md) to add them.
 
 ## Doubts solving
 
@@ -51,7 +51,7 @@ Please follow the next rules for the commit messages:
   - Add the content of the proposal, note that conformance tests are mandatory at this point.
   - Make a pull request.
   - The core dev can ask for changes before reaching the next stage.
-- Accepted: When the PR is merged into master.
+- Accepted: When the PR is merged into main.
 
 ## Tests
 
@@ -88,9 +88,8 @@ the target major/minor versions of the next release.
 
 ### Branches
 
-* `master`:
-TODO: Switch master to main, see [issue](https://github.com/Qiskit/openqasm/issues/327)
-The master branch is used for the development of the next OpenQASM release.
+* `main`:
+The main branch is used for the development of the next OpenQASM release.
 It is updated frequently and should not be considered stable. On the development
 branch, the language specification can and will change (possible breaking)
 as new language features are introduced and refined.
@@ -146,7 +145,7 @@ To trigger a bugfix release - `3.1.2`:
 2. Upon merger of the PR tag the HEAD of `stable/3.1` with `3.1.2` and push to Github.
 
 To trigger a minor release - `3.2.0`:
-1. Create a new stable branch `stable/3.2` using the current development branch as the base branch, eg., `git checkout -b stable/3.2 master`.
+1. Create a new stable branch `stable/3.2` using the current development branch as the base branch, eg., `git checkout -b stable/3.2 main`.
 2. Push this branch to Github.
 3. Tag the branch with `3.2.0` and push to Github.
 

README.md

@@ -94,7 +94,7 @@ This project is licensed under the Apache License 2.0 - see the [LICENSE] file f
 
 ## Contributing
 
-If you'd like to help please take a look to our [contribution guidelines](CONTRIBUTION.md). This project adheres to the Qiskit project's [code of conduct](https://github.com/Qiskit/qiskit/blob/master/CODE_OF_CONDUCT.md). By participating, you are expected to uphold this code.
+If you'd like to help please take a look to our [contribution guidelines](CONTRIBUTION.md). This project adheres to the Qiskit project's [code of conduct](https://github.com/Qiskit/qiskit/blob/main/CODE_OF_CONDUCT.md). By participating, you are expected to uphold this code.
 
 ## Release Notes
 

source/grammar/README.md

@@ -22,7 +22,7 @@ If you let `pip` do this automatically when it installs the reference parser, it
 
 ## Building the Python Parser
 
-1. Build the grammar files into the package directory with 
+1. Build the grammar files into the package directory with
     ```bash
     <antlr command> -o openqasm_reference_parser -Dlanguage=Python3 -visitor qasm3.g4
     ```

source/language/comments.rst

@@ -21,7 +21,7 @@ Version string
 The first non-comment line of an OpenQASM program may optionally be
 ``OPENQASM`` *M.m* ``;`` indicating a major version *M* and minor version *m*.
 More details on versioning and the release cycle for OpenQASM may be found
-`here <https://github.com/Qiskit/openqasm/blob/master/CONTRIBUTING.md>`_.
+`here <https://github.com/Qiskit/openqasm/blob/main/CONTRIBUTING.md>`_.
 
 The minor version number, expressed as a decimal point after the major version
 number followed by a number, is optional. If not present, the minor version