Summary

In this chapter, we learned that Puppet variables are different from those in normal procedural languages as they can only be assigned once. We saw that certain words are reserved and cannot be used in naming variables. We also saw that Puppet variables can be interpolated, depending on how and where strings are placed.

We covered various core data types and how they can be used to both restrict parameters and assign variables. We also looked at undef and Booleans, which need to be carefully managed when translating values to get the expected results.

Next, we looked at arrays and hashes and how to assign them. Although they can’t be changed, we learned how operators can manipulate them into new assignments. We also covered how arrays and hashes can be nested and mixed as hashes of arrays and arrays of hashes.

Then, we looked at abstract data types and how they apply restrictions to parameters more flexibly with the Sensitive type, which provides scoped protection...