Expressions

Everything inside the standard {{ }} block is an expression. Each block holds exactly one expression, but that expression can be chained with many individual operations. A quick overview:

• Math operations: + - * / % these operations are only valid with numeric types
• Equality: == != < <= > >= && ||
• Value setting: = the left side of this operation must be some identifier e.g. {{ some.val.path = 'hello world!' }}
• String concatenation: ~ e.g. {{ 'Hello' ~ ' ' ~ 'world!' }} prints "Hello world!"
• Functions: ident() e.g. {{ env('USER') }} would retrieve the value of the environment variable "USER".
• Filters: | e.g. {{ 'hello world' | upper }} would use the 'upper' filter to print "HELLO WORLD"

As documentation is still in progress, see the expression tests for examples of expression usage.