GHC.Hs.Expr

Post-Type checking Expression

PostTcExpr is an evidence expression attached to the syntax tree by the type checker (c.f. postTcType).

Post-Type checking Table

We use a PostTcTable where there are a bunch of pieces of evidence, more than is convenient to keep individually.

The function to use in rebindable syntax. See Note [NoSyntaxExpr].

An expression with wrappers, used for rebindable syntax

This should desugar to

syn_res_wrap $ syn_expr (syn_arg_wraps[0] arg0)
                        (syn_arg_wraps[1] arg1) ...

where the actual arguments come from elsewhere in the AST.

This is used for rebindable-syntax pieces that are too polymorphic for tcSyntaxOp (trS_fmap and the mzip in ParStmt)

Make a 'SyntaxExpr GhcRn' from an expression Used only in getMonadFailOp. See Note [Monad fail : Rebindable syntax, overloaded strings] in GHC.Rename.Expr

Make a SyntaxExpr from a Name (the "rn" is because this is used in the renamer).

HsWrap appears only in typechecker output

Pending Type-checker Splice

Pending Renamer Splice

Information about the parent of a record update:

• the parent type constructor or pattern synonym,

• the relevant con-likes,

• the field labels.

The different source constructs that we use to instantiate the "original" field in an `XXExprGhcRn original expansion`

Wrap a located expression with a PopErrCtxt

Wrap a located expression with a PopSrcExpr with an appropriate location

Build an expression using the extension constructor XExpr, and the two components of the expansion: original expression and expanded expressions.

Build an expression using the extension constructor XExpr, and the two components of the expansion: original do stmt and expanded expression

Build an expression using the extension constructor XExpr, and the two components of the expansion: original do stmt and expanded expression an associate with a provided location

Wrap the expanded version of the expression with a pop.

Build a XXExprGhcRn out of an extension constructor, and the two components of the expansion: original and expanded typechecked expressions.

Build a XXExprGhcRn out of an extension constructor. The two components of the expansion are: original statement and expanded typechecked expression.

hsExprNeedsParens p e returns True if the expression e needs parentheses under precedence p.

Parenthesize an expression without token information

parenthesizeHsExpr p e checks if hsExprNeedsParens p e is true, and if so, surrounds e with an HsPar. Otherwise, it simply returns e.

Command Syntax Table (for Arrow syntax)

Is there only one RHS in this list of matches?

Finalizers produced by a splice with addModFinalizer

See Note [Delaying modFinalizers in untyped splices] in GHC.Rename.Splice. For how this is used.