Module ast 

Abstract syntax representation. It’s mostly not actually a tree.

In the AST, terminology follows the TX-2 assembler’s documentation, and this doesn’t always match modern usage. In particular, “block” is used to refer to a contiguously-allocated sequence of instructions which share an origin statement. Such as the RC-block. This is not the same as a block in a language like C, where “block” is also a declaration-scoping construct.

Instead, in the TX-2 assembler, scopes are introduced by macro expansion. So, a “block” may contain some instructions followed by a macro-expansion (which has an associated scope) which itself might contain a macro-expansion, with another scope.

Modules

asteval 🔒

Evaluate (i.e. generate binary data from) parts of the AST.

Structs

ArithmeticExpression 🔒

Represents an arithmetic expression.

CommaDelimitedFragment 🔒

A component (usually a number) of an assembly-language instruction with possible leading or trailing commas.

ConfigValue 🔒

An expression used to specify the configuration bits of an instruction.

Equality 🔒

An “Equality” (modern term: assignment).

EqualityValue 🔒

The right-hand-side of an Equality.

FragmentWithHold 🔒

Part of a TX-2 instruction, convertible to a 36-bit value.

InstructionSequence 🔒

LiteralValue 🔒

Eventually we will support symbolic expressions.

RegistersContaining 🔒

SignedAtom 🔒

SpannedSymbolOrLiteral 🔒

Tag 🔒

A “Tag” is a symex used as a name for a place in a program. A tag is always terminated by an arrow (“->”) and [in the symbol table] it set to the numerical location of the word that it tags. [from section 6-2.2 of the User’s Handbook].

TaggedProgramInstruction 🔒

A TX-2 instruction with zero or more Tags.

UntaggedProgramInstruction 🔒

An instruction word in a TX-2 program.

Enums

Atom 🔒

A component of an arithmetic expression.

Commas 🔒

One, two or three commas.

CommasOrInstruction 🔒

An instruction fragment (FragmentWithHold) or one or more commas.

HoldBit 🔒

Indicates whether the hold bit is set, cleared or unspecified.

InstructionFragment 🔒

Part of a TX-2 instruction.

LocalSymbolTableBuildFailure 🔒

We failed to build a local symbol table.

OnUnboundMacroParameter 🔒

Indicates the action to be taken when a macro invocation does not specify a value for one of its dummy parameters.

Operator 🔒

The Users Handbook specifies that the operators are the four arithmetic operators (+-×/) and the logical operators ∧ (AND), ∨ (OR), and a circled ∨ meaning XOR.

Origin 🔒

Represents the origin of a block of program code.

RegisterContaining 🔒

An RC-word.

SymbolOrLiteral 🔒

A symbol name or a numeric literal, or #.

SymbolSubstitution 🔒

Indicates how some particular macro parameter should be processed.

SymbolUse 🔒

Records a reference to or definition of a symbol.

Traits

RcUpdater 🔒

Allows updates to the values of RC-words.

Functions

block_items_with_offset 🔒

Enumerate a sequence of items, decorating each with an Unsigned18Bit offset value.

elevated_string 🔒

Convert a normal string to subscript or superscript (or leave it as-is).

format_elevated_chars 🔒

Format a string in super/sub/normal script, using @...@ where necessary.

write_glyph_name 🔒

Write the name of a glyph with optional superscript / subscript indicator.