# alphabeta.sty

Greek symbols in text and math

Version:
  2.6 (changelog)
Copyright:
  © 2010, 2020, 2023 Günter Milde
Licence:

  This work may be distributed and/or modified under the conditions of the LaTeX Project Public License, either version 1.3 of this license or any later version.

Abstract

Use \alpha, \beta, ... for Greek letters in text and math mode.

## Motivation

By default, the \alpha, \beta, ... macros for Greek letters are only valid in mathematical mode.

With this package, the math macros are redefined to work in both, text and math mode, so that Greek letters can be specified with the established command names in text, too.

The package works with both, 8-bit TeX as well as Xe/LuaTeX. Under 8-bit TeX, literal Unicode characters can be used for Greek symbols in mathematical formulas.

Attention!

The macros work well in any font encoding for single symbols. However, with 8-bit TeX, the automatic font-encoding switches behind the doors interfere with kerning between letters and replacement of accent+character with a pre-composed character.

Therefore, Greek text should be written with the help of Babel or Polyglossia (setting the language to greek) or wrapped in the provided ensuregreek macro. Using Babel or Polyglossia also helps to ensure correct hyphenation and case changes.

## Usage

    \usepackage[<options>]{alphabeta}

The package provides the same options as textalpha.

### Conflicts

alphabeta does not work if the utf8x input encoding is selected. (utf8x is an interface to the ucs package which uses a non-compatible definition of \DeclareUnicodeCharacter.)

For details see alphabeta-doc.tex and alphabeta-doc.pdf.

## Implementation

### Identification

    \NeedsTeXFormat{LaTeX2e}
    \ProvidesPackage{alphabeta}
      [2023-11-16 2.6 macros for Greek letters in text and math]

### Requirements

This package extends the textalpha package. (Just like alphabeta, textalpha is part of greek-fontenc.) Package options are passed on to textalpha:

    \RequirePackageWithOptions{textalpha}

This package requires the e-TeX extensions (i.e. a not too old TeX distribution) for the \ifdefined test.

It uses the \TextOrMath test (in the LaTeX kernel since 2015). In case of an \TextOrMath undefined error, load the fixltx2e package.

### Postpone the re-definitions

To prevent other packages overwriting the re-defined commands we postpone the next steps until the start of the document body:

    \AtBeginDocument{

save @-catcode, allow @ in command names:

    \edef\RestoreAtCatcode{\catcode`@=\the\catcode`@\relax}%
    \makeatletter

### Save math macros

Map the standard math commands to maths-specific names:

    \let\mathGamma\Gamma
    \let\mathDelta\Delta
    \let\mathTheta\Theta
    \let\mathLambda\Lambda
    \let\mathXi\Xi
    \let\mathPi\Pi
    \let\mathSigma\Sigma
    \let\mathUpsilon\Upsilon
    \let\mathPhi\Phi
    \let\mathPsi\Psi
    \let\mathOmega\Omega
    %
    \let\mathalpha\alpha
    \let\mathbeta\beta
    \let\mathgamma\gamma
    \let\mathdelta\delta
    \let\mathepsilon\epsilon
    \let\mathvarepsilon\varepsilon
    \let\mathzeta\zeta
    \let\matheta\eta
    \let\maththeta\theta
    \let\mathvartheta\vartheta
    \let\mathiota\iota
    \let\mathkappa\kappa
    \let\mathlambda\lambda
    \let\mathmu\mu
    \let\mathnu\nu
    \let\mathxi\xi
    \let\mathpi\pi
    \let\mathvarpi\varpi
    \let\mathrho\rho
    \let\mathvarrho\varrho
    \let\mathsigma\sigma
    \let\mathvarsigma\varsigma
    \let\mathtau\tau
    \let\mathupsilon\upsilon
    \let\mathphi\phi
    \let\mathvarphi\varphi
    \let\mathchi\chi
    \let\mathpsi\psi
    \let\mathomega\omega
    % ``\digamma`` is defined by amsmath, provide a fallback
    \providecommand*{\digamma}{\textit{\textdigamma}}
    \let\mathdigamma\digamma

    % \varTheta, \varkappa, and \varbeta are defined by math packages
    \ifdefined\varTheta
      \let\mathvarTheta\varTheta
    \fi
    \ifdefined\varbeta
      \let\mathvarbeta\varbeta
    \fi
    \ifdefined\varkappa % e.g. with newtxmath
      \let\mathvarkappa\varkappa
    \fi

### Commands to access Greek letters by name

For letters defined in math mode, the commands work in both, text and math.

Some Greek letters look identical to Latin letters and can therefore not be used as variable symbols in math formulas. These letters are not defined in TeX’s math mode, we provide an alias to the corrsponding \text... command.

Mathematical notation distinguishes variant shape symbols for pi, phi, rho, theta (small and capital), beta, and kappa (characters for the latter three symbols are not included in TeX’s math fonts). These variations have no syntactic meaning in Greek text and are not given code-points in the LGR encoding while Unicode defines separate code points for the symbol variants.

#### Greek Alphabet

Macros keep their meaning in mathematical mode (i.e. use the same shape as without this package) and refer to GREEK LETTER … in text. For \epsilon and phi, this means that the selected symbol variant differs in text vs. math mode. Use \varepsilon and \varphi (see section variant shape symbols below) to select the “GREEK LETTER …” in both, text and math mode.

Macros for letters that can take diacritical marks and are used in text and math mode must be made robust to ensure the selection of pre-composed characters and correct case changes with \MakeUppercase and \MakeLowercase. We use \DeclareRobustCommand because \renewrobustcmd from the etoolbox leads to errors in PDF-strings.

    \providecommand*{\Alpha}{\textAlpha}
    \providecommand*{\Beta}{\textBeta}
    \renewcommand*{\Gamma}{\TextOrMath{\textGamma}{\mathGamma}}
    \renewcommand*{\Delta}{\TextOrMath{\textDelta}{\mathDelta}}
    \providecommand*{\Epsilon}{\textEpsilon}
    \providecommand*{\Zeta}{\textZeta}
    \providecommand*{\Eta}{\textEta}
    \renewcommand*{\Theta}{\TextOrMath{\textTheta}{\mathTheta}}
    \providecommand*{\Iota}{\textIota}
    \providecommand*{\Kappa}{\textKappa}
    \renewcommand*{\Lambda}{\TextOrMath{\textLambda}{\mathLambda}}
    \providecommand*{\Mu}{\textMu}
    \providecommand*{\Nu}{\textNu}
    \renewcommand*{\Xi}{\TextOrMath{\textXi}{\mathXi}}
    \providecommand*{\Omicron}{\textOmicron}
    \renewcommand*{\Pi}{\TextOrMath{\textPi}{\mathPi}}
    \providecommand*{\Rho}{\textRho}
    \renewcommand*{\Sigma}{\TextOrMath{\textSigma}{\mathSigma}}
    \providecommand*{\Tau}{\textTau}
    \DeclareRobustCommand{\Upsilon}{\TextOrMath{\textUpsilon}{\mathUpsilon}}
    \renewcommand*{\Phi}{\TextOrMath{\textPhi}{\mathPhi}}
    \providecommand*{\Chi}{\textChi}
    \renewcommand*{\Psi}{\TextOrMath{\textPsi}{\mathPsi}}
    \DeclareRobustCommand{\Omega}{\TextOrMath{\textOmega}{\mathOmega}}
    %
    \DeclareRobustCommand{\alpha}{\TextOrMath{\textalpha}{\mathalpha}}
    \renewcommand*{\beta}{\TextOrMath{\textbeta}{\mathbeta}}
    \renewcommand*{\gamma}{\TextOrMath{\textgamma}{\mathgamma}}
    \renewcommand*{\delta}{\TextOrMath{\textdelta}{\mathdelta}}
    \DeclareRobustCommand{\epsilon}{\TextOrMath{\textepsilon}{\mathepsilon}} % ε/ϵ
    \renewcommand*{\zeta}{\TextOrMath{\textzeta}{\mathzeta}}
    \DeclareRobustCommand{\eta}{\TextOrMath{\texteta}{\matheta}}
    \renewcommand*{\theta}{\TextOrMath{\texttheta}{\maththeta}}
    \DeclareRobustCommand{\iota}{\TextOrMath{\textiota}{\mathiota}}
    \renewcommand*{\kappa}{\TextOrMath{\textkappa}{\mathkappa}}
    \renewcommand*{\lambda}{\TextOrMath{\textlambda}{\mathlambda}}
    \renewcommand*{\mu}{\TextOrMath{\textmu}{\mathmu}}
    \renewcommand*{\nu}{\TextOrMath{\textnu}{\mathnu}}
    \renewcommand*{\xi}{\TextOrMath{\textxi}{\mathxi}}
    \providecommand*{\omicron}{\textomicron}
    \renewcommand*{\pi}{\TextOrMath{\textpi}{\mathpi}}
    \DeclareRobustCommand{\rho}{\TextOrMath{\textrho}{\mathrho}}
    \renewcommand*{\sigma}{\TextOrMath{\textsigma}{\mathsigma}}
    \providecommand*{\finalsigma}{\TextOrMath{\textfinalsigma}{\mathvarsigma}}
    \renewcommand*{\varsigma}{\finalsigma}
    \renewcommand*{\tau}{\TextOrMath{\texttau}{\mathtau}}
    \DeclareRobustCommand{\upsilon}{\TextOrMath{\textupsilon}{\mathupsilon}}
    \renewcommand*{\phi}{\TextOrMath{\textphi}{\mathphi}}             % ϕ/φ
    \renewcommand*{\chi}{\TextOrMath{\textchi}{\mathchi}}
    \renewcommand*{\psi}{\TextOrMath{\textpsi}{\mathpsi}}
    \DeclareRobustCommand{\omega}{\TextOrMath{\textomega}{\mathomega}}

#### Archaic letters

    \renewcommand*{\digamma}{\TextOrMath{\textdigamma}{\mathdigamma}} % ϝ
    \providecommand*{\Digamma}{\textDigamma}     % Ϝ
    \providecommand*{\stigma}{\textstigma}       % ϛ
    \providecommand*{\varstigma}{\textvarstigma} % stigma variant (CB.enc, teubner)
    \providecommand*{\koppa}{\textkoppa}         % ϟ (greek small letter koppa)
    \providecommand*{\Koppa}{\textKoppa}         % Ϟ (greek letter koppa)
    % !! babel-greek defines \qoppa as alias for ϟ (\textkoppa)!
    \def\qoppa{\textqoppa}                       % ϙ (archaic koppa)
    \providecommand*{\Qoppa}{\textQoppa}         % Ϙ (archaic Koppa)
    \providecommand*{\Stigma}{\textStigma}       % Ϛ (in some fonts ϹΤ ligature)
    \providecommand*{\Sampi}{\textSampi}         % Ϡ
    \providecommand*{\sampi}{\textsampi}         % ϡ

#### Variant shape symbols

TeX’s concept of “standard” vs. “variant” math symbols does not map to the distinction between GREEK LETTER … vs. GREEK … SYMBOL in the Unicode standard (see test-tuenc-greek.pdf).

The \...symbol macros select the GREEK … SYMBOL in both, text and math mode. For \epsilonsymbol and \phisymbol this is the default shape in math mode. The \var... macros select the shape used by TeX math (or, if not supported, the SYMBOL shape):

    % ..symbol == var..
    \renewcommand*{\varpi}{\TextOrMath{\textpisymbol}{\mathvarpi}}          % ϖ
    \providecommand*{\pisymbol}{\varpi}                                     % ϖ
    \renewcommand*{\varrho}{\TextOrMath{\textrhosymbol}{\mathvarrho}}       % ϱ
    \providecommand*{\rhosymbol}{\TextOrMath{\textrhosymbol}{\mathvarrho}}  % ϱ
    \renewcommand*{\vartheta}{\TextOrMath{\textthetasymbol}{\mathvartheta}} % ϑ
    \providecommand*{\thetasymbol}{\vartheta}                               % ϑ
    % ..symbol != var..
    \renewcommand*{\varepsilon}{\TextOrMath{\textepsilon}{\mathvarepsilon}} % ε
    \providecommand*{\epsilonsymbol}{\TextOrMath{\textepsilonsymbol}{\mathepsilon}} % ϵ
    \renewcommand*{\varphi}{\TextOrMath{\textphi}{\mathvarphi}}             % φ
    \providecommand*{\phisymbol}{\TextOrMath{\textphisymbol}{\mathphi}}     % ϕ
    % only text (in standard 8-bit TeX, may be defined with additional packages):
    \ifdefined\mathvarbeta
      \renewcommand*{\varbeta}{\TextOrMath{\textbetasymbol}{\mathvarbeta}}  % ϐ
    \else
      \providecommand*{\varbeta}{\textbetasymbol}
    \fi
    \providecommand*{\betasymbol}{\varbeta}
    \ifdefined\mathvarkappa                                                 % ϰ
      \renewcommand*{\varkappa}{\TextOrMath{\textkappasymbol}{\mathvarkappa}}
    \else
      \providecommand*{\varkappa}{\textkappasymbol}
    \fi
    \providecommand*{\kappasymbol}{\varkappa}
    % ..symbol != var.. (in "amsmath", \varTheta is italic shape of \Theta)
    \ifdefined\mathvarTheta
      \renewcommand*{\varTheta}{\TextOrMath{\textTheta}{\mathvarTheta}}
    \else
      \providecommand*{\varTheta}{\textTheta}                               % Θ
    \fi
    \providecommand*{\Thetasymbol}{\textThetasymbol}                        % ϴ

### TextCompositeCommands for the letter-name macros

The NFSS TextComposite mechanism looks for the next token without expanding it. In order to let compositions like \ensuregreek{\'\Alpha} or \ensuregreek{\>"\alpha} work as expected we define TextComposites with the letter name commands.

TextCompositeCommands are always specific for the font-encoding. Documents may use TU, LGR, and PU in parallel. We define auxiliary commands with definitions that are required by more than one font encoding.

#### Select pre-composed characters.

Required by LGR and PU.

With TU, most pre-composed characters are selected by the the engine. (Actually by the Harfbuzz renderer which is default for XeTeX and can be selected with fontspec for LuaTeX).

    \newcommand*{\alphabeta@select@precomposed}[1]{
      \DeclareTextCompositeCommand{\accvaria               }{#1}{\alpha  }{\accvaria\textalpha}
      \DeclareTextCompositeCommand{\accdasia               }{#1}{\alpha  }{\accdasia\textalpha}
      \DeclareTextCompositeCommand{\accpsili               }{#1}{\alpha  }{\accpsili\textalpha}
      \DeclareTextCompositeCommand{\accdasiavaria          }{#1}{\alpha  }{\accdasiavaria\textalpha}
      \DeclareTextCompositeCommand{\acctonos               }{#1}{\alpha  }{\acctonos\textalpha}
      \DeclareTextCompositeCommand{\accdasiaoxia           }{#1}{\alpha  }{\accdasiaoxia\textalpha}
      \DeclareTextCompositeCommand{\accpsilioxia           }{#1}{\alpha  }{\accpsilioxia\textalpha}
      \DeclareTextCompositeCommand{\accpsilivaria          }{#1}{\alpha  }{\accpsilivaria\textalpha}
      \DeclareTextCompositeCommand{\accperispomeni         }{#1}{\alpha  }{\accperispomeni\textalpha}
      \DeclareTextCompositeCommand{\accdasiaperispomeni    }{#1}{\alpha  }{\accdasiaperispomeni\textalpha}
      \DeclareTextCompositeCommand{\accpsiliperispomeni    }{#1}{\alpha  }{\accpsiliperispomeni\textalpha}
      \DeclareTextCompositeCommand{\accvaria               }{#1}{\eta    }{\accvaria\texteta}
      \DeclareTextCompositeCommand{\accdasia               }{#1}{\eta    }{\accdasia\texteta}
      \DeclareTextCompositeCommand{\accpsili               }{#1}{\eta    }{\accpsili\texteta}
      \DeclareTextCompositeCommand{\acctonos               }{#1}{\eta    }{\acctonos\texteta}
      \DeclareTextCompositeCommand{\accdasiaoxia           }{#1}{\eta    }{\accdasiaoxia\texteta}
      \DeclareTextCompositeCommand{\accpsilioxia           }{#1}{\eta    }{\accpsilioxia\texteta}
      \DeclareTextCompositeCommand{\accdasiavaria          }{#1}{\eta    }{\accdasiavaria\texteta}
      \DeclareTextCompositeCommand{\accperispomeni         }{#1}{\eta    }{\accperispomeni\texteta}
      \DeclareTextCompositeCommand{\accdasiaperispomeni    }{#1}{\eta    }{\accdasiaperispomeni\texteta}
      \DeclareTextCompositeCommand{\accpsiliperispomeni    }{#1}{\eta    }{\accpsiliperispomeni\texteta}
      \DeclareTextCompositeCommand{\accpsilivaria          }{#1}{\eta    }{\accpsilivaria\texteta}
      \DeclareTextCompositeCommand{\accvaria               }{#1}{\omega  }{\accvaria\textomega}
      \DeclareTextCompositeCommand{\accdasia               }{#1}{\omega  }{\accdasia\textomega}
      \DeclareTextCompositeCommand{\accpsili               }{#1}{\omega  }{\accpsili\textomega}
      \DeclareTextCompositeCommand{\accdasiavaria          }{#1}{\omega  }{\accdasiavaria\textomega}
      \DeclareTextCompositeCommand{\acctonos               }{#1}{\omega  }{\acctonos\textomega}
      \DeclareTextCompositeCommand{\accdasiaoxia           }{#1}{\omega  }{\accdasiaoxia\textomega}
      \DeclareTextCompositeCommand{\accpsilioxia           }{#1}{\omega  }{\accpsilioxia\textomega}
      \DeclareTextCompositeCommand{\accpsilivaria          }{#1}{\omega  }{\accpsilivaria\textomega}
      \DeclareTextCompositeCommand{\accperispomeni         }{#1}{\omega  }{\accperispomeni\textomega}
      \DeclareTextCompositeCommand{\accdasiaperispomeni    }{#1}{\omega  }{\accdasiaperispomeni\textomega}
      \DeclareTextCompositeCommand{\accpsiliperispomeni    }{#1}{\omega  }{\accpsiliperispomeni\textomega}
      \DeclareTextCompositeCommand{\accvaria               }{#1}{\iota   }{\accvaria\textiota}
      \DeclareTextCompositeCommand{\accdasia               }{#1}{\iota   }{\accdasia\textiota}
      \DeclareTextCompositeCommand{\accpsili               }{#1}{\iota   }{\accpsili\textiota}
      \DeclareTextCompositeCommand{\accdasiavaria          }{#1}{\iota   }{\accdasiavaria\textiota}
      \DeclareTextCompositeCommand{\acctonos               }{#1}{\iota   }{\acctonos\textiota}
      \DeclareTextCompositeCommand{\accdasiaoxia           }{#1}{\iota   }{\accdasiaoxia\textiota}
      \DeclareTextCompositeCommand{\accpsilioxia           }{#1}{\iota   }{\accpsilioxia\textiota}
      \DeclareTextCompositeCommand{\accpsilivaria          }{#1}{\iota   }{\accpsilivaria\textiota}
      \DeclareTextCompositeCommand{\accperispomeni         }{#1}{\iota   }{\accperispomeni\textiota}
      \DeclareTextCompositeCommand{\accdasiaperispomeni    }{#1}{\iota   }{\accdasiaperispomeni\textiota}
      \DeclareTextCompositeCommand{\accpsiliperispomeni    }{#1}{\iota   }{\accpsiliperispomeni\textiota}
      \DeclareTextCompositeCommand{\accdialytika           }{#1}{\iota   }{\accdialytika\textiota}
      \DeclareTextCompositeCommand{\accdialytikavaria      }{#1}{\iota   }{\accdialytikavaria\textiota}
      \DeclareTextCompositeCommand{\accdialytikatonos      }{#1}{\iota   }{\accdialytikatonos\textiota}
      \DeclareTextCompositeCommand{\accdialytikaperispomeni}{#1}{\iota   }{\accdialytikaperispomeni\textiota}
      \DeclareTextCompositeCommand{\accvaria               }{#1}{\upsilon}{\accvaria\textupsilon}
      \DeclareTextCompositeCommand{\accdasia               }{#1}{\upsilon}{\accdasia\textupsilon}
      \DeclareTextCompositeCommand{\accpsili               }{#1}{\upsilon}{\accpsili\textupsilon}
      \DeclareTextCompositeCommand{\accdasiavaria          }{#1}{\upsilon}{\accdasiavaria\textupsilon}
      \DeclareTextCompositeCommand{\acctonos               }{#1}{\upsilon}{\acctonos\textupsilon}
      \DeclareTextCompositeCommand{\accdasiaoxia           }{#1}{\upsilon}{\accdasiaoxia\textupsilon}
      \DeclareTextCompositeCommand{\accpsilioxia           }{#1}{\upsilon}{\accpsilioxia\textupsilon}
      \DeclareTextCompositeCommand{\accpsilivaria          }{#1}{\upsilon}{\accpsilivaria\textupsilon}
      \DeclareTextCompositeCommand{\accperispomeni         }{#1}{\upsilon}{\accperispomeni\textupsilon}
      \DeclareTextCompositeCommand{\accdasiaperispomeni    }{#1}{\upsilon}{\accdasiaperispomeni\textupsilon}
      \DeclareTextCompositeCommand{\accpsiliperispomeni    }{#1}{\upsilon}{\accpsiliperispomeni\textupsilon}
      \DeclareTextCompositeCommand{\accdialytika           }{#1}{\upsilon}{\accdialytika\textupsilon}
      \DeclareTextCompositeCommand{\accdialytikavaria      }{#1}{\upsilon}{\accdialytikavaria\textupsilon}
      \DeclareTextCompositeCommand{\accdialytikatonos      }{#1}{\upsilon}{\accdialytikatonos\textupsilon}
      \DeclareTextCompositeCommand{\accdialytikaperispomeni}{#1}{\upsilon}{\accdialytikaperispomeni\textupsilon}
      \DeclareTextCompositeCommand{\accvaria               }{#1}{\epsilon}{\accvaria\textepsilon}
      \DeclareTextCompositeCommand{\accdasia               }{#1}{\epsilon}{\accdasia\textepsilon}
      \DeclareTextCompositeCommand{\accpsili               }{#1}{\epsilon}{\accpsili\textepsilon}
      \DeclareTextCompositeCommand{\accdasiavaria          }{#1}{\epsilon}{\accdasiavaria\textepsilon}
      \DeclareTextCompositeCommand{\acctonos               }{#1}{\epsilon}{\acctonos\textepsilon}
      \DeclareTextCompositeCommand{\accdasiaoxia           }{#1}{\epsilon}{\accdasiaoxia\textepsilon}
      \DeclareTextCompositeCommand{\accpsilioxia           }{#1}{\epsilon}{\accpsilioxia\textepsilon}
      \DeclareTextCompositeCommand{\accpsilivaria          }{#1}{\epsilon}{\accpsilivaria\textepsilon}
      \DeclareTextCompositeCommand{\accvaria               }{#1}{\omicron}{\accvaria\textomicron}
      \DeclareTextCompositeCommand{\accdasia               }{#1}{\omicron}{\accdasia\textomicron}
      \DeclareTextCompositeCommand{\accpsili               }{#1}{\omicron}{\accpsili\textomicron}
      \DeclareTextCompositeCommand{\accdasiavaria          }{#1}{\omicron}{\accdasiavaria\textomicron}
      \DeclareTextCompositeCommand{\acctonos               }{#1}{\omicron}{\acctonos\textomicron}
      \DeclareTextCompositeCommand{\accdasiaoxia           }{#1}{\omicron}{\accdasiaoxia\textomicron}
      \DeclareTextCompositeCommand{\accpsilioxia           }{#1}{\omicron}{\accpsilioxia\textomicron}
      \DeclareTextCompositeCommand{\accpsilivaria          }{#1}{\omicron}{\accpsilivaria\textomicron}
      %
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Alpha  }{\accdasia\textAlpha}
      \DeclareTextCompositeCommand{\accdasiavaria      }{#1}{\Alpha  }{\accdasiavaria\textAlpha}
      \DeclareTextCompositeCommand{\accdasiaoxia       }{#1}{\Alpha  }{\accdasiaoxia\textAlpha}
      \DeclareTextCompositeCommand{\accdasiaperispomeni}{#1}{\Alpha  }{\accdasiaperispomeni\textAlpha}
      \DeclareTextCompositeCommand{\accpsili           }{#1}{\Alpha  }{\accpsili\textAlpha}
      \DeclareTextCompositeCommand{\accpsilivaria      }{#1}{\Alpha  }{\accpsilivaria\textAlpha}
      \DeclareTextCompositeCommand{\accpsilioxia       }{#1}{\Alpha  }{\accpsilioxia\textAlpha}
      \DeclareTextCompositeCommand{\accpsiliperispomeni}{#1}{\Alpha  }{\accpsiliperispomeni\textAlpha}
      \DeclareTextCompositeCommand{\acctonos           }{#1}{\Alpha  }{\acctonos\textAlpha}
      \DeclareTextCompositeCommand{\accvaria           }{#1}{\Alpha  }{\accvaria\textAlpha}
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Epsilon}{\accdasia\textEpsilon}
      \DeclareTextCompositeCommand{\accdasiaoxia       }{#1}{\Epsilon}{\accdasiaoxia\textEpsilon}
      \DeclareTextCompositeCommand{\accdasiavaria      }{#1}{\Epsilon}{\accdasiavaria\textEpsilon}
      \DeclareTextCompositeCommand{\accpsili           }{#1}{\Epsilon}{\accpsili\textEpsilon}
      \DeclareTextCompositeCommand{\accpsilioxia       }{#1}{\Epsilon}{\accpsilioxia\textEpsilon}
      \DeclareTextCompositeCommand{\accpsilivaria      }{#1}{\Epsilon}{\accpsilivaria\textEpsilon}
      \DeclareTextCompositeCommand{\acctonos           }{#1}{\Epsilon}{\acctonos\textEpsilon}
      \DeclareTextCompositeCommand{\accvaria           }{#1}{\Epsilon}{\accvaria\textEpsilon}
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Eta    }{\accdasia\textEta}
      \DeclareTextCompositeCommand{\accdasiavaria      }{#1}{\Eta    }{\accdasiavaria\textEta}
      \DeclareTextCompositeCommand{\accdasiaoxia       }{#1}{\Eta    }{\accdasiaoxia\textEta}
      \DeclareTextCompositeCommand{\accdasiaperispomeni}{#1}{\Eta    }{\accdasiaperispomeni\textEta}
      \DeclareTextCompositeCommand{\accpsili           }{#1}{\Eta    }{\accpsili\textEta}
      \DeclareTextCompositeCommand{\accpsilivaria      }{#1}{\Eta    }{\accpsilivaria\textEta}
      \DeclareTextCompositeCommand{\accpsilioxia       }{#1}{\Eta    }{\accpsilioxia\textEta}
      \DeclareTextCompositeCommand{\accpsiliperispomeni}{#1}{\Eta    }{\accpsiliperispomeni\textEta}
      \DeclareTextCompositeCommand{\acctonos           }{#1}{\Eta    }{\acctonos\textEta}
      \DeclareTextCompositeCommand{\accvaria           }{#1}{\Eta    }{\accvaria\textEta}
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Iota   }{\accdasia\textIota}
      \DeclareTextCompositeCommand{\accdasiavaria      }{#1}{\Iota   }{\accdasiavaria\textIota}
      \DeclareTextCompositeCommand{\accdasiaoxia       }{#1}{\Iota   }{\accdasiaoxia\textIota}
      \DeclareTextCompositeCommand{\accdasiaperispomeni}{#1}{\Iota   }{\accdasiaperispomeni\textIota}
      \DeclareTextCompositeCommand{\accdialytika       }{#1}{\Iota   }{\accdialytika\textIota}
      \DeclareTextCompositeCommand{\accpsili           }{#1}{\Iota   }{\accpsili\textIota}
      \DeclareTextCompositeCommand{\accpsilivaria      }{#1}{\Iota   }{\accpsilivaria\textIota}
      \DeclareTextCompositeCommand{\accpsilioxia       }{#1}{\Iota   }{\accpsilioxia\textIota}
      \DeclareTextCompositeCommand{\accpsiliperispomeni}{#1}{\Iota   }{\accpsiliperispomeni\textIota}
      \DeclareTextCompositeCommand{\acctonos           }{#1}{\Iota   }{\acctonos\textIota}
      \DeclareTextCompositeCommand{\accvaria           }{#1}{\Iota   }{\accvaria\textIota}
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Omicron}{\accdasia\textOmicron}
      \DeclareTextCompositeCommand{\accdasiavaria      }{#1}{\Omicron}{\accdasiavaria\textOmicron}
      \DeclareTextCompositeCommand{\accdasiaoxia       }{#1}{\Omicron}{\accdasiaoxia\textOmicron}
      \DeclareTextCompositeCommand{\accpsili           }{#1}{\Omicron}{\accpsili\textOmicron}
      \DeclareTextCompositeCommand{\accpsilivaria      }{#1}{\Omicron}{\accpsilivaria\textOmicron}
      \DeclareTextCompositeCommand{\accpsilioxia       }{#1}{\Omicron}{\accpsilioxia\textOmicron}
      \DeclareTextCompositeCommand{\acctonos           }{#1}{\Omicron}{\acctonos\textOmicron}
      \DeclareTextCompositeCommand{\accvaria           }{#1}{\Omicron}{\accvaria\textOmicron}
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Upsilon}{\accdasia\textUpsilon}
      \DeclareTextCompositeCommand{\accdasiavaria      }{#1}{\Upsilon}{\accdasiavaria\textUpsilon}
      \DeclareTextCompositeCommand{\accdasiaoxia       }{#1}{\Upsilon}{\accdasiaoxia\textUpsilon}
      \DeclareTextCompositeCommand{\accdasiaperispomeni}{#1}{\Upsilon}{\accdasiaperispomeni\textUpsilon}
      \DeclareTextCompositeCommand{\accdialytika       }{#1}{\Upsilon}{\accdialytika\textUpsilon}
      \DeclareTextCompositeCommand{\acctonos           }{#1}{\Upsilon}{\acctonos\textUpsilon}
      \DeclareTextCompositeCommand{\accvaria           }{#1}{\Upsilon}{\accvaria\textUpsilon}
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Rho    }{\accdasia\textRho}
      \DeclareTextCompositeCommand{\accdasia           }{#1}{\Omega  }{\accdasia\textOmega}
      \DeclareTextCompositeCommand{\accdasiavaria      }{#1}{\Omega  }{\accdasiavaria\textOmega}
      \DeclareTextCompositeCommand{\accdasiaoxia       }{#1}{\Omega  }{\accdasiaoxia\textOmega}
      \DeclareTextCompositeCommand{\accdasiaperispomeni}{#1}{\Omega  }{\accdasiaperispomeni\textOmega}
      \DeclareTextCompositeCommand{\accpsili           }{#1}{\Omega  }{\accpsili\textOmega}
      \DeclareTextCompositeCommand{\accpsilivaria      }{#1}{\Omega  }{\accpsilivaria\textOmega}
      \DeclareTextCompositeCommand{\accpsilioxia       }{#1}{\Omega  }{\accpsilioxia\textOmega}
      \DeclareTextCompositeCommand{\accpsiliperispomeni}{#1}{\Omega  }{\accpsiliperispomeni\textOmega}
      \DeclareTextCompositeCommand{\acctonos           }{#1}{\Omega  }{\acctonos\textOmega}
      \DeclareTextCompositeCommand{\accvaria           }{#1}{\Omega  }{\accvaria\textOmega}
    }

#### Drop “capital” accents

Definitions in babel-greek let \MakeUppercase convert standard accents \', \` ``, ``\~, and \" to “capital” versions.

In LGR, the “capital” accents are generally dropped. In PU and TU, they must be kept on Latin letters but dropped from Greek letters:

    \newcommand*{\alphabeta@drop@capital@accents}[1]{
      \DeclareTextCompositeCommand{\accACUTE}{#1}{\Alpha  }{\alphabeta@alpha@hiatus}
      \DeclareTextCompositeCommand{\accACUTE}{#1}{\Epsilon}{\alphabeta@epsilon@hiatus}
      \DeclareTextCompositeCommand{\accACUTE}{#1}{\Eta    }{\textEta    }
      \DeclareTextCompositeCommand{\accACUTE}{#1}{\Iota   }{\textIota   }
      \DeclareTextCompositeCommand{\accACUTE}{#1}{\Upsilon}{\textUpsilon}
      \DeclareTextCompositeCommand{\accACUTE}{#1}{\Omega  }{\textOmega  }
      %
      \DeclareTextCompositeCommand{\accGRAVE}{#1}{\Alpha  }{\textAlpha  }
      \DeclareTextCompositeCommand{\accGRAVE}{#1}{\Epsilon}{\textEpsilon}
      \DeclareTextCompositeCommand{\accGRAVE}{#1}{\Eta    }{\textEta    }
      \DeclareTextCompositeCommand{\accGRAVE}{#1}{\Iota   }{\textIota   }
      \DeclareTextCompositeCommand{\accGRAVE}{#1}{\Upsilon}{\textUpsilon}
      \DeclareTextCompositeCommand{\accGRAVE}{#1}{\Omega  }{\textOmega  }
      %
      \DeclareTextCompositeCommand{\accTILDE}{#1}{\Alpha  }{\textAlpha  }
      \DeclareTextCompositeCommand{\accTILDE}{#1}{\Eta    }{\textEta    }
      \DeclareTextCompositeCommand{\accTILDE}{#1}{\Iota   }{\textIota   }
      \DeclareTextCompositeCommand{\accTILDE}{#1}{\Upsilon}{\textUpsilon}
      \DeclareTextCompositeCommand{\accTILDE}{#1}{\Omega  }{\textOmega  }
    }

#### Hiatus feature

Look ahead and place a diaeresis on Ι or Υ. Leads to errors in PU.

    \newcommand*{\alphabeta@hiatus@composites}[1]{
      \DeclareTextCommand{\alphabeta@alpha@hiatus}{#1}{%
        \csname LGR@ifnextchar\endcsname {\Iota}{\Alpha\"}{%
          \csname LGR@ifnextchar\endcsname {\Upsilon}{\Alpha\"}{\Alpha}%
        }%
      }
      \DeclareTextCommand{\alphabeta@epsilon@hiatus}{#1}{%
        \csname LGR@ifnextchar\endcsname {\Iota}{\Epsilon\"}{%
          \csname LGR@ifnextchar\endcsname {\Upsilon}{\Epsilon\"}{\Epsilon}%
        }%
      }
      \DeclareTextCompositeCommand{\LGR@hiatus}{#1}{\Alpha}{\alphabeta@alpha@hiatus}
      \DeclareTextCompositeCommand{\LGR@hiatus}{#1}{\Epsilon}{\alphabeta@epsilon@hiatus}
    }

#### Composites for TU

With font encoding TU, pre-composed characters are selected by the the Harfbuzz renderer (default for XeTeX, select with fontspec for LuaTeX). Exception: the (standard) combining tilde.

    \@ifl@aded{def}{tuenc-greek}{
      \DeclareUnicodeComposite{\~}{\alpha  }{"1FB6} % ᾶ
      \DeclareUnicodeComposite{\~}{\eta    }{"1FC6} % ῆ
      \DeclareUnicodeComposite{\~}{\iota   }{"1FD6} % ῖ
      \DeclareUnicodeComposite{\~}{\upsilon}{"1FE6} % ῦ
      \DeclareUnicodeComposite{\~}{\omega  }{"1FF6} % ῶ

      \alphabeta@drop@capital@accents{\UnicodeEncodingName}
      \alphabeta@hiatus@composites{\UnicodeEncodingName}
    }{}

#### Composites for LGR

    \@ifl@aded{def}{lgrenc}{
      \alphabeta@select@precomposed{LGR}
      \alphabeta@hiatus@composites{LGR}
    }{}

#### Composites for PU

Load composite defs:

    \@ifl@aded{def}{puenc}{

      \alphabeta@select@precomposed{PU}
      \alphabeta@drop@capital@accents{PU}

The hiatus feature leads to errors in PU:

      \DeclareTextCompositeCommand{\LGR@hiatus}{PU}{\Alpha}{\textAlpha}
      \DeclareTextCompositeCommand{\LGR@hiatus}{PU}{\Epsilon}{\textEpsilon}
      % fix ``\'\alpha`` and ``\'\epsilon`` (\'{\alpha} works):
      \DeclareTextCompositeCommand{\accACUTE}{PU}{\Alpha  }{\textAlpha}
      \DeclareTextCompositeCommand{\accACUTE}{PU}{\Epsilon}{\textEpsilon}
    }{}

Drop auxiliary definitions to free memory:

    \renewcommand*{\alphabeta@select@precomposed  }{\relax}
    \renewcommand*{\alphabeta@drop@capital@accents}{\relax}
    \renewcommand*{\alphabeta@hiatus@composites   }{\relax}

### Case changing

We need to extend the case-mapping \@uclclist for characters that are defined with \DeclareTextCommandDefault.

The definition of an auxiliary, self-resetting macro makes this idempotent (only the first use of this function will expand the @uclclist). The second and third lines are TeX’s way of writing @uclclist += ….

Since 2022, \MakeUppercase expects the default for ambiguous mappings in first position, before, the default was in last position.

    \providecommand*\alphabeta@update@uclclist{%
      \expandafter\def\expandafter\@uclclist\expandafter{%
        \@uclclist
        \alpha         \Alpha
        \epsilon       \Epsilon
        \epsilonsymbol \Epsilon
        \varepsilon    \Epsilon
        \eta           \Eta
        \iota          \Iota
        \omicron       \Omicron
        \rho           \Rho
        \varrho        \Rho
        \rhosymbol     \Rho
        \upsilon       \Upsilon
        \omega         \Omega
        % repeat default for pre-2022 \MakeUppercase
        \epsilon       \Epsilon
        \rho           \Rho
       }%
      \let\alphabeta@update@uclclist\relax
    }

Expand the @uclclist using the just defined macro:

    \alphabeta@update@uclclist

### Re-definition for Greek Unicode input in math mode

Map Greek characters that are also defined in math mode to the letter-name macros:

    \ifdefined\DeclareUnicodeCharacter
      \DeclareUnicodeCharacter{0393}{\Gamma}         % Γ
      \DeclareUnicodeCharacter{0394}{\Delta}         % Δ
      \DeclareUnicodeCharacter{0398}{\Theta}         % Θ
      \DeclareUnicodeCharacter{039B}{\Lambda}        % Λ
      \DeclareUnicodeCharacter{039E}{\Xi}            % Ξ
      \DeclareUnicodeCharacter{03A0}{\Pi}            % Π
      \DeclareUnicodeCharacter{03A3}{\Sigma}         % Σ
      \DeclareUnicodeCharacter{03A5}{\Upsilon}       % Υ
      \DeclareUnicodeCharacter{03A6}{\Phi}           % Φ
      \DeclareUnicodeCharacter{03A8}{\Psi}           % Ψ
      \DeclareUnicodeCharacter{03A9}{\Omega}         % Ω

      \DeclareUnicodeCharacter{03B1}{\alpha}         % α
      \DeclareUnicodeCharacter{03B2}{\beta}          % β
      \DeclareUnicodeCharacter{03B3}{\gamma}         % γ
      \DeclareUnicodeCharacter{03B4}{\delta}         % δ
      \DeclareUnicodeCharacter{03B5}{\varepsilon}    % ε textepsilon/varepsilon
      \DeclareUnicodeCharacter{03B6}{\zeta}          % ζ
      \DeclareUnicodeCharacter{03B7}{\eta}           % η
      \DeclareUnicodeCharacter{03B8}{\theta}         % θ
      \DeclareUnicodeCharacter{03B9}{\iota}          % ι
      \DeclareUnicodeCharacter{03BA}{\kappa}         % κ
      \DeclareUnicodeCharacter{03BB}{\lambda}        % λ
      \DeclareUnicodeCharacter{03BC}{\mu}            % μ
      \DeclareUnicodeCharacter{03BD}{\nu}            % ν
      \DeclareUnicodeCharacter{03BE}{\xi}            % ξ
      \DeclareUnicodeCharacter{03C0}{\pi}            % π
      \DeclareUnicodeCharacter{03C1}{\rho}           % ρ
      \DeclareUnicodeCharacter{03C2}{\finalsigma}    % ς
      \DeclareUnicodeCharacter{03C3}{\sigma}         % σ
      \DeclareUnicodeCharacter{03C4}{\tau}           % τ
      \DeclareUnicodeCharacter{03C5}{\upsilon}       % υ
      \DeclareUnicodeCharacter{03C6}{\varphi}        % φ textphi/varphi
      \DeclareUnicodeCharacter{03C7}{\chi}           % χ
      \DeclareUnicodeCharacter{03C8}{\psi}           % ψ
      \DeclareUnicodeCharacter{03C9}{\omega}         % ω

      \DeclareUnicodeCharacter{03D1}{\thetasymbol}   % ϑ
      \DeclareUnicodeCharacter{03D5}{\phisymbol}     % ϕ $\phi$
      \DeclareUnicodeCharacter{03D6}{\pisymbol}      % ϖ
      \DeclareUnicodeCharacter{03DD}{\digamma}       % ϝ
      \DeclareUnicodeCharacter{03F1}{\rhosymbol}     % ϱ
      \DeclareUnicodeCharacter{03F5}{\epsilonsymbol} % ϵ $\epsilon$
    \fi

    \RestoreAtCatcode
    } % close the \AtBeginDocument macro

## Changelog

0.1 | 2012-06-26 | initial version
0.2 | 2013-05-03 | new accent macro names with lgrxenc.def 0.7
0.3 | 2013-05-28 | use lgrenc.def from greek-fontenc,
|  | enable Unicode input in math mode.
0.4 | 2013-09-11 | move to greek-fontenc, support XeTeX/LuaTeX.
0.13 | 2015-09-04 | Support for variant symbols.
0.13.2 | 2016-02-05 | Support for standard Unicode text font encoding “TU” (new in fontspec v2.5a).
0.14 | 2020/02/28 | rename alphabeta-euenc.def to alphabeta-tuenc.def.
1.0 | 2020/09/25 | New package version. No changes in this file.
2.0 | 2020/10/13 | Provide \Koppa.
2.2.1 | 2023-03-08 | Documentation update.
2.5 | 2023-09-12 | Fixes for \MakeUppercase / \MakeLowercase.
|  | Text mode alias \varTheta → \Theta.
|  | Overwrite legacy babel-greek alias \qoppa (ϟ) with \textqoppa (ϙ).
|  | Inline alphabeta-tuenc.def and alphabeta-lgr.def (dropping redundant composite definitions).
|  | Composite definitions to select pre-composed characters in PU (PDF strings).
2.6 | 2023-11-16 | Don’t use TextCommands for generic macros (fixes warnings in math mode and errors with bm).