Bash.AST.TestExpression (Bash v0.3.0)

Test expression for [[ ... ]] conditional constructs.

This represents bash's extended test expression using double bracket notation. The expression tokens are passed directly to the test expression builtin for evaluation.

Examples

# [[ -f file ]]
%TestExpression{
  expression: ["-f", "file"]
}

# [[ $x -eq 5 ]]
%TestExpression{
  expression: [%Word{...}, "-eq", "5"]
}

# [[ -f file1 && -f file2 ]]
%TestExpression{
  expression: ["-f", "file1", "&&", "-f", "file2"]
}

Expressions are composed of the same primaries used by the test builtin, and may be combined using the following operators:

( EXPRESSION ) - Returns the value of EXPRESSION
! EXPRESSION - True if EXPRESSION is false; else false
EXPR1 && EXPR2 - True if both EXPR1 and EXPR2 are true; else false
EXPR1 || EXPR2 - True if either EXPR1 or EXPR2 is true; else false

When the == and != operators are used, the string to the right of the operator is used as a pattern and pattern matching is performed. When the =~ operator is used, the string to the right of the operator is matched as a regular expression.

The && and || operators do not evaluate EXPR2 if EXPR1 is sufficient to determine the expression's value.

Exit Status: 0 or 1 depending on value of EXPRESSION.

Operator precedence: ! > && > ||

Reference: https://cgit.git.savannah.gnu.org/cgit/bash.git/plain/builtins/test.def?h=bash-5.3

Summary

Types

t()

Types

t()

@type t() :: %Bash.AST.TestExpression{
  exit_code: 0..255 | nil,
  expression: [Bash.AST.Word.t() | String.t()],
  meta: Bash.AST.Meta.t(),
  state_updates: map()
}