Document how fromJSON can return a JSON data type (#17285)

Co-authored-by: Lucas Costi <lucascosti@users.noreply.github.com>

Author: Sarah Edwards

content/actions/reference/context-and-expression-syntax-for-github-actions.md

@@ -186,27 +186,27 @@ jobs:
     steps:
       - name: Dump GitHub context
         env:
-          GITHUB_CONTEXT: ${{ toJson(github) }}
+          GITHUB_CONTEXT: ${{ toJSON(github) }}
         run: echo "$GITHUB_CONTEXT"
       - name: Dump job context
         env:
-          JOB_CONTEXT: ${{ toJson(job) }}
+          JOB_CONTEXT: ${{ toJSON(job) }}
         run: echo "$JOB_CONTEXT"
       - name: Dump steps context
         env:
-          STEPS_CONTEXT: ${{ toJson(steps) }}
+          STEPS_CONTEXT: ${{ toJSON(steps) }}
         run: echo "$STEPS_CONTEXT"
       - name: Dump runner context
         env:
-          RUNNER_CONTEXT: ${{ toJson(runner) }}
+          RUNNER_CONTEXT: ${{ toJSON(runner) }}
         run: echo "$RUNNER_CONTEXT"
       - name: Dump strategy context
         env:
-          STRATEGY_CONTEXT: ${{ toJson(strategy) }}
+          STRATEGY_CONTEXT: ${{ toJSON(strategy) }}
         run: echo "$STRATEGY_CONTEXT"
       - name: Dump matrix context
         env:
-          MATRIX_CONTEXT: ${{ toJson(matrix) }}
+          MATRIX_CONTEXT: ${{ toJSON(matrix) }}
         run: echo "$MATRIX_CONTEXT"
 ```
 {% endraw %}
@@ -348,7 +348,7 @@ The value for `array` can be an array or a string. All values in `array` are con
 
 `join(github.event.issue.labels.*.name, ', ')` may return 'bug, help wanted'
 
-#### toJson
+#### toJSON
 
 `toJSON(value)`
 
@@ -358,13 +358,13 @@ Returns a pretty-print JSON representation of `value`. You can use this function
 
 `toJSON(job)` might return `{ "status": "Success" }`
 
-#### fromJson
+#### fromJSON
 
 `fromJSON(value)`
 
-Returns a JSON object for `value`. You can use this function to provide a JSON object as an evaluated expression.
+Returns a JSON object or JSON data type for `value`. You can use this function to provide a JSON object as an evaluated expression or to convert environment variables from a string.
 
-##### Example
+##### Example returning a JSON object
 
 This workflow sets a JSON matrix in one job, and passes it to the next job using an output and `fromJSON`.
 
@@ -384,12 +384,33 @@ jobs:
     needs: job1
     runs-on: ubuntu-latest
     strategy:
-      matrix: ${{fromJson(needs.job1.outputs.matrix)}}
+      matrix: ${{fromJSON(needs.job1.outputs.matrix)}}
     steps:
     - run: build
 ```
 {% endraw %}
 
+##### Example returning a JSON data type
+
+This workflow uses `fromJSON` to convert environment variables from a string to a Boolean or integer.
+
+{% raw %}
+```yaml
+name: print
+on: push
+env: 
+  continue: true
+  time: 3
+jobs:
+  job1:
+    runs-on: ubuntu-latest
+    steps:
+    - continue-on-error: ${{ fromJSON(env.continue) }}
+      timeout-minutes: ${{ fromJSON(env.time) }}
+      run: echo ...
+```
+{% endraw %}
+
 #### hashFiles
 
 `hashFiles(path)`